Merged revisions 285373 via svnmerge from

https://origsvn.digium.com/svn/asterisk/branches/1.8

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  r285373 | tilghman | 2010-09-07 16:14:03 -0500 (Tue, 07 Sep 2010) | 7 lines
  
  Add CHANNEL(checkhangup) to check whether a channel is in the process of being hanged up.
  
  (closes issue #17652)
   Reported by: kobaz
   Patches: 
         func_channel.patch uploaded by kobaz (license 834)
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git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@285374 65c4cc65-6c06-0410-ace0-fbb531ad65f3