[WFLY-3436] Synch webservices subsystem with WFLY master [8.x]

This is basically the subset of ws related commits included in https://github.com/wildfly/wildfly/pull/6257/commits, that is what was originally developed in Kabir's wildfly-next branch and merged to master after 8.1.0 tag. This stuff *must* go into any minor and major release following 8.1.