Consolidate generation of various server control commands

This is needed for better switchover control, so we can instruct
the remote repmgr to issue the appropriate server command rather
than trying to work out what it should be from the local node.

dbutils.h

@@ -254,6 +254,9 @@ typedef struct
 
 #define T_CONFIGFILE_LIST_INITIALIZER { 0, 0, NULL }
 
+
+/* global variables */
+
 extern int			server_version_num;
 
 /* macros */
@@ -412,5 +415,6 @@ void 		 get_bdr_other_node_name(PGconn *conn, int node_id, char *name_buf);
 
 bool		 am_bdr_failover_handler(PGconn *conn, int node_id);
 void		 unset_bdr_failover_handler(PGconn *conn);
-#endif /* dbutils.h */
+
+#endif /* _REPMGR_DBUTILS_H_ */