MINOR: ssl: support ssl keyword for dynamic servers

Activate the 'ssl' keyword for dynamic servers. This is the final step
to have ssl dynamic servers feature implemented. If activated,
ssl_sock_prepare_srv_ctx will be called at the end of the 'add server'
CLI handler.

At the same time, update the management doc to list all ssl keywords
implemented for dynamic servers.
diff --git a/doc/management.txt b/doc/management.txt
index 932981b..7abfc85 100644
--- a/doc/management.txt
+++ b/doc/management.txt
@@ -1472,13 +1472,25 @@
 
   Here is the list of the currently supported keywords :
 
+  - allow-0rtt
+  - alpn
   - backup
+  - ca-file
+  - ciphers
+  - ciphersuites
+  - crl-file
+  - crt
   - disabled
   - enabled
+  - force-sslv3/tlsv10/tlsv11/tlsv12/tlsv13
   - id
   - maxconn
   - maxqueue
   - minconn
+  - no-ssl-reuse
+  - no-sslv3/tlsv10/tlsv11/tlsv12/tlsv13
+  - no-tls-tickets
+  - npn
   - pool-low-conn
   - pool-max-conn
   - pool-purge-delay
@@ -1486,9 +1498,18 @@
   - proxy-v2-options
   - send-proxy
   - send-proxy-v2
+  - send-proxy-v2-ssl
+  - send-proxy-v2-ssl-cn
+  - sni
   - source
+  - ssl
+  - ssl-max-ver
+  - ssl-min-ver
   - tfo
+  - tls-tickets
   - usesrc
+  - verify
+  - verifyhost
   - weight
 
   Their syntax is similar to the server line from the configuration file,