BUG/MINOR: contrib/prometheus-exporter: Rename some metrics

The following metrics have been renamed without the "_http" part :

 * http_queue_time_average_seconds     => queue_time_average_seconds
 * http_connect_time_average_seconds   => connect_time_average_seconds
 * http_response_time_average_seconds  => response_time_average_seconds
 * http_total_time_average_seconds     => total_time_average_seconds

These metrics are reported per backend and per server and are not specific to
HTTP sessions.

(cherry picked from commit 68b6968ecd4e265526cbef28bdd8ba7c941ce7bf)
Signed-off-by: Christopher Faulet <cfaulet@haproxy.com>
diff --git a/contrib/prometheus-exporter/README b/contrib/prometheus-exporter/README
index 6467ffe..b6160b3 100644
--- a/contrib/prometheus-exporter/README
+++ b/contrib/prometheus-exporter/README
@@ -166,13 +166,13 @@
 | haproxy_backend_connection_reuses_total             | Total number of connection reuses.                                       |
 | haproxy_backend_bytes_in_total                      | Current total of incoming bytes.                                         |
 | haproxy_backend_bytes_out_total                     | Current total of outgoing bytes.                                         |
-| haproxy_backend_http_queue_time_average_seconds     | Avg. queue time for last 1024 successful connections.                    |
-| haproxy_backend_http_connect_time_average_seconds   | Avg. connect time for last 1024 successful connections.                  |
-| haproxy_backend_http_response_time_average_seconds  | Avg. response time for last 1024 successful connections.                 |
-| haproxy_backend_http_total_time_average_seconds     | Avg. total time for last 1024 successful connections.                    |
+| haproxy_backend_queue_time_average_seconds          | Avg. queue time for last 1024 successful connections.                    |
+| haproxy_backend_connect_time_average_seconds        | Avg. connect time for last 1024 successful connections.                  |
+| haproxy_backend_response_time_average_seconds       | Avg. response time for last 1024 successful connections. (0 for TCP)     |
+| haproxy_backend_total_time_average_seconds          | Avg. total time for last 1024 successful connections.                    |
 | haproxy_backend_max_queue_time_seconds              | Maximum observed queue time.                                             |
 | haproxy_backend_max_connect_time_seconds            | Maximum observed connect time.                                           |
-| haproxy_backend_max_response_time_seconds           | Maximum observed response time.                                          |
+| haproxy_backend_max_response_time_seconds           | Maximum observed response time. (0 for TCP)                              |
 | haproxy_backend_max_total_time_seconds              | Maximum observed total time.                                             |
 | haproxy_backend_requests_denied_total               | Total number of denied requests.                                         |
 | haproxy_backend_responses_denied_total              | Total number of denied responses.                                        |
@@ -217,13 +217,13 @@
 | haproxy_server_queue_limit                         | Configured maxqueue for the server (0 meaning no limit).                  |
 | haproxy_server_bytes_in_total                      | Current total of incoming bytes.                                          |
 | haproxy_server_bytes_out_total                     | Current total of outgoing bytes.                                          |
-| haproxy_server_http_queue_time_average_seconds     | Avg. queue time for last 1024 successful connections.                     |
-| haproxy_server_http_connect_time_average_seconds   | Avg. connect time for last 1024 successful connections.                   |
-| haproxy_server_http_response_time_average_seconds  | Avg. response time for last 1024 successful connections.                  |
-| haproxy_server_http_total_time_average_seconds     | Avg. total time for last 1024 successful connections.                     |
+| haproxy_server_queue_time_average_seconds          | Avg. queue time for last 1024 successful connections.                     |
+| haproxy_server_connect_time_average_seconds        | Avg. connect time for last 1024 successful connections.                   |
+| haproxy_server_response_time_average_seconds       | Avg. response time for last 1024 successful connections. (0 for TCP)      |
+| haproxy_server_total_time_average_seconds          | Avg. total time for last 1024 successful connections.                     |
 | haproxy_server_max_queue_time_seconds              | Maximum observed queue time.                                              |
 | haproxy_server_max_connect_time_seconds            | Maximum observed connect time.                                            |
-| haproxy_server_max_response_time_seconds           | Maximum observed response time.                                           |
+| haproxy_server_max_response_time_seconds           | Maximum observed response time.  (0 for TCP)                              |
 | haproxy_server_max_total_time_seconds              | Maximum observed total time.                                              |
 | haproxy_server_connection_attempts_total           | Total number of connection establishment attempts.                        |
 | haproxy_server_connection_reuses_total             | Total number of connection reuses.                                        |
diff --git a/contrib/prometheus-exporter/service-prometheus.c b/contrib/prometheus-exporter/service-prometheus.c
index 1991823..a657d11 100644
--- a/contrib/prometheus-exporter/service-prometheus.c
+++ b/contrib/prometheus-exporter/service-prometheus.c
@@ -556,10 +556,10 @@
 	[ST_F_LASTSESS]       = IST("last_session_seconds"),
 	[ST_F_LAST_CHK]       = IST("check_last_content"),
 	[ST_F_LAST_AGT]       = IST("agentcheck_last_content"),
-	[ST_F_QTIME]          = IST("http_queue_time_average_seconds"),
-	[ST_F_CTIME]          = IST("http_connect_time_average_seconds"),
-	[ST_F_RTIME]          = IST("http_response_time_average_seconds"),
-	[ST_F_TTIME]          = IST("http_total_time_average_seconds"),
+	[ST_F_QTIME]          = IST("queue_time_average_seconds"),
+	[ST_F_CTIME]          = IST("connect_time_average_seconds"),
+	[ST_F_RTIME]          = IST("response_time_average_seconds"),
+	[ST_F_TTIME]          = IST("total_time_average_seconds"),
 	[ST_F_AGENT_STATUS]   = IST("agentcheck_status"),
 	[ST_F_AGENT_CODE]     = IST("agentcheck_code"),
 	[ST_F_AGENT_DURATION] = IST("agentcheck_duration_milliseconds"),