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
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Merged revisions 404318 from http://svn.asterisk.org/svn/asterisk/branches/11
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Merged revisions 404320 from http://svn.asterisk.org/svn/asterisk/branches/12


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@404321 65c4cc65-6c06-0410-ace0-fbb531ad65f3