Remove router_options

Relaced router_options with configuration parameters in the createInstance
router entry point. The same needs to be done for the filter API as barely
any filters use the feature.

Some routers (binlogrouter) still support router_options but using it is
deprecated. This had to be done as their use wasn't deprecated in 2.2.

include/maxscale/service.h

@@ -129,7 +129,6 @@ typedef struct service
     SERV_LISTENER *ports;              /**< Linked list of ports and protocols
                                         * that this service will listen on */
     char *routerModule;                /**< Name of router module to use */
-    char **routerOptions;              /**< Router specific option strings */
     struct mxs_router_object *router;  /**< The router we are using */
     struct mxs_router *router_instance;/**< The router instance for this service */
     char version_string[MAX_SERVICE_VERSION_LEN]; /**< version string for this service listeners */