Blocked revisions 239718 via svnmerge

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  r239718 | dvossel | 2010-01-13 11:16:12 -0600 (Wed, 13 Jan 2010) | 23 lines
  
  add silence gen to wait apps
    
  asterisk.conf's 'transmit_silence' option existed before
  this patch, but was limited to only generating silence
  while recording and sending DTMF. Now enabling the
  transmit_silence option generates silence during wait
  times as well.
    
  To achieve this, ast_safe_sleep has been modified to
  generate silence anytime no other generators are present
  and transmit_silence is enabled. Wait apps not using
  ast_safe_sleep now generate silence when transmit_silence
  is enabled as well.
  
  (closes issue 0016524)
  Reported by: kobaz
  
  (closes issue 0016523)
  Reported by: kobaz
  Tested by: dvossel
    
  Review: https://reviewboard.asterisk.org/r/456/
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git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@239719 65c4cc65-6c06-0410-ace0-fbb531ad65f3