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.
Readconnroute can now be configured at runtime. The changes to
configuration processing allow the removal of router_options now that the
parameters are parsed inside the router.