MODCLUSTER-331

WIP implementation of MODCLUSTER-331

* missing startup dependencies
* missing connector statistics (already have some ideas from David)
* probably will reintroduce the factories
* add/remove server+host handling
* https://issues.jboss.org/browse/UNDERTOW-18
* https://issues.jboss.org/browse/UNDERTOW-19
* https://issues.jboss.org/browse/UNDERTOW-20