KAZOO-1208: update pull request to support backward compatibility
3.12: upgrade cowboy to 0.10.0 and refresh Crossbar
3.12: fix nksip pulling in older versions of libs
3.12: build wsock before nksip
KAZOO-2646 - delete unwanted line
KAZOO-2647: add an enabled flag to the error emails
KAZOO-2647: keep the naming consistant in system_config
Merge remote-tracking branch 'upstream/3.12' into 3.12