update docs for mysql check

docs/20_Checks/check_mysqlserver.md

@@ -7,7 +7,7 @@ The kind of check is defined by a parameter `-m METHOD`.
 
 ## Requirements
 
-* mysql (cli tool)
+* ``mysql`` (mysql client as cli tool)
 * The icinga user needs to connect to the database server (see Installation).
 
 ## Syntax
@@ -161,3 +161,7 @@ As root run
 ```
 
 This drops the database user `icingaclient` and removes the config file `/etc/icingaclient/.my.cnf`.
+
+## Graph
+
+See templates for mysql graphs in <https://git-repo.iml.unibe.ch/iml-open-source/icinga-graphite-templates>.