DOC: contrib/prometheus-exporter: Add missing metrics in README

Some metrics were missing (haproxy_process_uptime_seconds and
haproxy_process_build_info). To ease the review against the service output,
the same order is used in the README.
diff --git a/contrib/prometheus-exporter/README b/contrib/prometheus-exporter/README
index 65902bf..a859815 100644
--- a/contrib/prometheus-exporter/README
+++ b/contrib/prometheus-exporter/README
@@ -117,10 +117,7 @@
 | haproxy_process_nbthread                       |
 | haproxy_process_nbproc                         |
 | haproxy_process_relative_process_id            |
-| haproxy_process_start_time_seconds             |
-| haproxy_process_max_memory_bytes               |
-| haproxy_process_pool_allocated_bytes           |
-| haproxy_process_pool_used_bytes                |
+| haproxy_process_uptime_seconds                 |
 | haproxy_process_pool_failures_total            |
 | haproxy_process_max_fds                        |
 | haproxy_process_max_sockets                    |
@@ -172,6 +169,11 @@
 | haproxy_process_spliced_bytes_out_total        |
 | haproxy_process_bytes_out_rate                 |
 | haproxy_process_recv_logs_total                |
+| haproxy_process_build_info                     |
+| haproxy_process_max_memory_bytes               |
+| haproxy_process_pool_allocated_bytes           |
+| haproxy_process_pool_used_bytes                |
+| haproxy_process_start_time_seconds             |
 +------------------------------------------------+
 
 * Frontend metrics
@@ -179,34 +181,33 @@
 +-------------------------------------------------+
 |    Metric name                                  |
 +-------------------------------------------------+
-| haproxy_frontend_status                         |
 | haproxy_frontend_current_sessions               |
 | haproxy_frontend_max_sessions                   |
 | haproxy_frontend_limit_sessions                 |
 | haproxy_frontend_sessions_total                 |
-| haproxy_frontend_limit_session_rate             |
-| haproxy_frontend_max_session_rate               |
-| haproxy_frontend_connections_rate_current       |
-| haproxy_frontend_connections_rate_max           |
-| haproxy_frontend_connections_total              |
 | haproxy_frontend_bytes_in_total                 |
 | haproxy_frontend_bytes_out_total                |
 | haproxy_frontend_requests_denied_total          |
 | haproxy_frontend_responses_denied_total         |
 | haproxy_frontend_request_errors_total           |
-| haproxy_frontend_denied_connections_total       |
-| haproxy_frontend_denied_sessions_total          |
-| haproxy_frontend_failed_header_rewriting_total  |
+| haproxy_frontend_status                         |
+| haproxy_frontend_limit_session_rate             |
+| haproxy_frontend_max_session_rate               |
+| haproxy_frontend_http_responses_total           |
 | haproxy_frontend_http_requests_rate_max         |
 | haproxy_frontend_http_requests_total            |
-| haproxy_frontend_http_responses_total           |
-| haproxy_frontend_intercepted_requests_total     |
-| haproxy_frontend_http_cache_lookups_total       |
-| haproxy_frontend_http_cache_hits_total          |
 | haproxy_frontend_http_comp_bytes_in_total       |
 | haproxy_frontend_http_comp_bytes_out_total      |
 | haproxy_frontend_http_comp_bytes_bypassed_total |
 | haproxy_frontend_http_comp_responses_total      |
+| haproxy_frontend_connections_rate_max           |
+| haproxy_frontend_connections_total              |
+| haproxy_frontend_intercepted_requests_total     |
+| haproxy_frontend_denied_connections_total       |
+| haproxy_frontend_denied_sessions_total          |
+| haproxy_frontend_failed_header_rewriting_total  |
+| haproxy_frontend_http_cache_lookups_total       |
+| haproxy_frontend_http_cache_hits_total          |
 | haproxy_frontend_internal_errors_total          |
 +-------------------------------------------------+
 
@@ -215,53 +216,53 @@
 +-----------------------------------------------------+
 |    Metric name                                      |
 +-----------------------------------------------------+
-| haproxy_backend_status                              |
+| haproxy_backend_current_queue                       |
+| haproxy_backend_max_queue                           |
 | haproxy_backend_current_sessions                    |
 | haproxy_backend_max_sessions                        |
 | haproxy_backend_limit_sessions                      |
 | haproxy_backend_sessions_total                      |
-| haproxy_backend_max_session_rate                    |
-| haproxy_backend_last_session_seconds                |
-| haproxy_backend_current_queue                       |
-| haproxy_backend_max_queue                           |
-| haproxy_backend_connection_attempts_total           |
-| haproxy_backend_connection_reuses_total             |
 | haproxy_backend_bytes_in_total                      |
 | haproxy_backend_bytes_out_total                     |
-| haproxy_backend_queue_time_average_seconds          |
-| haproxy_backend_connect_time_average_seconds        |
-| haproxy_backend_response_time_average_seconds       |
-| haproxy_backend_total_time_average_seconds          |
-| haproxy_backend_max_queue_time_seconds              |
-| haproxy_backend_max_connect_time_seconds            |
-| haproxy_backend_max_response_time_seconds           |
-| haproxy_backend_max_total_time_seconds              |
 | haproxy_backend_requests_denied_total               |
 | haproxy_backend_responses_denied_total              |
 | haproxy_backend_connection_errors_total             |
 | haproxy_backend_response_errors_total               |
 | haproxy_backend_retry_warnings_total                |
 | haproxy_backend_redispatch_warnings_total           |
-| haproxy_backend_failed_header_rewriting_total       |
-| haproxy_backend_client_aborts_total                 |
-| haproxy_backend_server_aborts_total                 |
+| haproxy_backend_status                              |
 | haproxy_backend_weight                              |
-| haproxy_backend_uweight                             |
 | haproxy_backend_active_servers                      |
 | haproxy_backend_backup_servers                      |
 | haproxy_backend_check_up_down_total                 |
 | haproxy_backend_check_last_change_seconds           |
 | haproxy_backend_downtime_seconds_total              |
 | haproxy_backend_loadbalanced_total                  |
-| haproxy_backend_http_requests_total                 |
+| haproxy_backend_max_session_rate                    |
 | haproxy_backend_http_responses_total                |
-| haproxy_backend_http_cache_lookups_total            |
-| haproxy_backend_http_cache_hits_total               |
+| haproxy_backend_http_requests_total                 |
+| haproxy_backend_client_aborts_total                 |
+| haproxy_backend_server_aborts_total                 |
 | haproxy_backend_http_comp_bytes_in_total            |
 | haproxy_backend_http_comp_bytes_out_total           |
 | haproxy_backend_http_comp_bytes_bypassed_total      |
 | haproxy_backend_http_comp_responses_total           |
+| haproxy_backend_last_session_seconds                |
+| haproxy_backend_queue_time_average_seconds          |
+| haproxy_backend_connect_time_average_seconds        |
+| haproxy_backend_response_time_average_seconds       |
+| haproxy_backend_total_time_average_seconds          |
+| haproxy_backend_failed_header_rewriting_total       |
+| haproxy_backend_connection_attempts_total           |
+| haproxy_backend_connection_reuses_total             |
+| haproxy_backend_http_cache_lookups_total            |
+| haproxy_backend_http_cache_hits_total               |
+| haproxy_backend_max_queue_time_seconds              |
+| haproxy_backend_max_connect_time_seconds            |
+| haproxy_backend_max_response_time_seconds           |
+| haproxy_backend_max_total_time_seconds              |
 | haproxy_backend_internal_errors_total               |
+| haproxy_backend_uweight                             |
 +-----------------------------------------------------+
 
 * Server metrics
@@ -269,53 +270,53 @@
 +----------------------------------------------------+
 |    Metric name                                     |
 +----------------------------------------------------+
-| haproxy_server_status                              |
+| haproxy_server_current_queue                       |
+| haproxy_server_max_queue                           |
 | haproxy_server_current_sessions                    |
 | haproxy_server_max_sessions                        |
 | haproxy_server_limit_sessions                      |
 | haproxy_server_sessions_total                      |
-| haproxy_server_max_session_rate                    |
-| haproxy_server_last_session_seconds                |
-| haproxy_server_current_queue                       |
-| haproxy_server_max_queue                           |
-| haproxy_server_queue_limit                         |
 | haproxy_server_bytes_in_total                      |
 | haproxy_server_bytes_out_total                     |
-| haproxy_server_queue_time_average_seconds          |
-| haproxy_server_connect_time_average_seconds        |
-| haproxy_server_response_time_average_seconds       |
-| haproxy_server_total_time_average_seconds          |
-| haproxy_server_max_queue_time_seconds              |
-| haproxy_server_max_connect_time_seconds            |
-| haproxy_server_max_response_time_seconds           |
-| haproxy_server_max_total_time_seconds              |
-| haproxy_server_connection_attempts_total           |
-| haproxy_server_connection_reuses_total             |
 | haproxy_server_responses_denied_total              |
 | haproxy_server_connection_errors_total             |
 | haproxy_server_response_errors_total               |
 | haproxy_server_retry_warnings_total                |
 | haproxy_server_redispatch_warnings_total           |
-| haproxy_server_failed_header_rewriting_total       |
-| haproxy_server_client_aborts_total                 |
-| haproxy_server_server_aborts_total                 |
+| haproxy_server_status                              |
 | haproxy_server_weight                              |
-| haproxy_server_uweight                             |
-| haproxy_server_check_status                        |
-| haproxy_server_check_code                          |
-| haproxy_server_check_duration_seconds              |
 | haproxy_server_check_failures_total                |
 | haproxy_server_check_up_down_total                 |
-| haproxy_server_downtime_seconds_total              |
 | haproxy_server_check_last_change_seconds           |
+| haproxy_server_downtime_seconds_total              |
+| haproxy_server_queue_limit                         |
 | haproxy_server_current_throttle                    |
 | haproxy_server_loadbalanced_total                  |
+| haproxy_server_max_session_rate                    |
+| haproxy_server_check_status                        |
+| haproxy_server_check_code                          |
+| haproxy_server_check_duration_seconds              |
 | haproxy_server_http_responses_total                |
+| haproxy_server_client_aborts_total                 |
+| haproxy_server_server_aborts_total                 |
+| haproxy_server_last_session_seconds                |
+| haproxy_server_queue_time_average_seconds          |
+| haproxy_server_connect_time_average_seconds        |
+| haproxy_server_response_time_average_seconds       |
+| haproxy_server_total_time_average_seconds          |
+| haproxy_server_failed_header_rewriting_total       |
+| haproxy_server_connection_attempts_total           |
+| haproxy_server_connection_reuses_total             |
 | haproxy_server_idle_connections_current            |
 | haproxy_server_idle_connections_limit              |
+| haproxy_server_max_queue_time_seconds              |
+| haproxy_server_max_connect_time_seconds            |
+| haproxy_server_max_response_time_seconds           |
+| haproxy_server_max_total_time_seconds              |
 | haproxy_server_internal_errors_total               |
 | haproxy_server_unsafe_idle_connections_current     |
 | haproxy_server_safe_idle_connections_current       |
 | haproxy_server_used_connections_current            |
 | haproxy_server_need_connections_current            |
+| haproxy_server_uweight                             |
 +----------------------------------------------------+