MXS-1398: Clean up mysql.h header

Cleaned up the MaxScale version of the mysql.h header by removing all
unused includes. This revealed a large amount of dependencies on these
removed includes in other files which needed to be fixed.

Also sorted all includes in changed files by type and alphabetical
order. Removed explicit revision history from modified files.

server/modules/authenticator/MySQLBackendAuth/mysql_backend_auth.c

@@ -20,20 +20,14 @@
  * The "heavy lifting" of the authentication is done by the protocol module so
  * the only thing left for this module is to read the final OK packet from the
  * server.
- *
- * @verbatim
- * Revision History
- * Date         Who                     Description
- * 27/09/2016   Markus Makela           Initial version
- *
- * @endverbatim
  */
 
 #define MXS_MODULE_NAME "MySQLBackendAuth"
 
+#include <maxscale/alloc.h>
 #include <maxscale/authenticator.h>
 #include <maxscale/protocol/mysql.h>
-#include <maxscale/alloc.h>
+#include <maxscale/server.h>
 #include <maxscale/utils.h>
 
 /** Authentication states */