Explicitly check caller hangup in app Queue rather than a polluted res2 value.

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Merged revisions 369262 from http://svn.asterisk.org/svn/asterisk/branches/1.8
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Merged revisions 369263 from http://svn.asterisk.org/svn/asterisk/branches/10


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@369264 65c4cc65-6c06-0410-ace0-fbb531ad65f3