Merge missing bugfix for issue #11583

Merge missing bugfix for issue #11583

This is the combination of two commits that made it into 1.4, 1.6.0,
1.6.1, and trunk (and therefor 1.8) but that was missed for 1.6.2.

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  r183386 | dvossel | 2009-03-19 14:40:07 -0500 (Thu, 19 Mar 2009) | 6 lines

  Cleaning up a few things in detect disconnect patch

  Initialized ast_call_feature in detect_disconnect to avoid accessing uninitialized memory.  Cleaned up /param tags in features.h.  No longer send dynamic features in ast_feature_detect.

  issue #11583
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  r183126 | dvossel | 2009-03-19 11:15:16 -0500 (Thu, 19 Mar 2009) | 17 lines

  Allow disconnect feature before a call is bridged

  feature.conf has a disconnect option.  By default this option is set to '*', but it could be anything.  If a user wishes to disconnect a call before the other side answers, only '*' will work, regardless if the disconnect option is set to something else.  This is because features are unavailable until bridging takes place.  The default disconnect option, '*', was hardcoded in app_dial, which doesn't make any sense from a user perspective since they may expect it to be something different.  This patch allows features to be detected from outside of the bridge, but not operated on.  In this case, the disconnect feature can be detected before briding and handled outside of features.c.

  (closes issue #11583)
  Reported by: sobomax
  Patches:
  	patch-apps__app_dial.c uploaded by sobomax (license 359)
  	11583.latest-patch uploaded by murf (license 17)
  	detect_disconnect.diff uploaded by dvossel (license 671)
  Tested by: sobomax, dvossel
  Review: http://reviewboard.digium.com/r/195/
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git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/1.6.2@308677 65c4cc65-6c06-0410-ace0-fbb531ad65f3