Handle temporary failures on gk registration

Introduce new 'stopped' state for gk client and restart gk client
on failures
Remove ooh323 stack command lock as it is not need now.
(closes issue ASTERISK-21960)
Reported by: Dmitry Melekhov
Patches:
	ASTERISK-21960.patch
	ASTERISK-21960-stacklockup-2.patch
Tested by: Dmitry Melekhov



git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/11@404318 65c4cc65-6c06-0410-ace0-fbb531ad65f3