Merged revisions 180006 via svnmerge from

Merged revisions 180006 via svnmerge from
https://origsvn.digium.com/svn/asterisk/branches/1.4

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  r180006 | mmichelson | 2009-03-03 16:48:18 -0600 (Tue, 03 Mar 2009) | 17 lines

  Clarify some documentation of queues.conf.sample

  It had always been possible to explicitly specify a "blank"
  value for a sound file in queues.conf and have no sound played
  back. The problem with this is that it would result in some ugly
  CLI warnings from file.c.

  This commit introduces a check when playing a file in app_queue
  to see if the name of the file is zero-length and return early if
  that is the case. Also, the ability to specify the blank sound
  files in queues.conf is now mentioned more clearly in queues.conf.sample

  (closes issue #14227)
  Reported by: caspy
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git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@180007 65c4cc65-6c06-0410-ace0-fbb531ad65f3