Merged revisions 323370 via svnmerge from

Merged revisions 323370 via svnmerge from
https://origsvn.digium.com/svn/asterisk/branches/1.8

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  r323370 | twilson | 2011-06-14 09:33:55 -0700 (Tue, 14 Jun 2011) | 10 lines

  Add rtpkeepalives back to 1.8

  The RTP-engine conversion left out support for handling rtpkeepalives.
  This patch adds them back.

  (closes issue ASTERISK-17304)
  Reported by: lmadsen

  Review: https://reviewboard.asterisk.org/r/1226/
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git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@323374 65c4cc65-6c06-0410-ace0-fbb531ad65f3