Merged revisions 335064 via svnmerge from

Merged revisions 335064 via svnmerge from
https://origsvn.digium.com/svn/asterisk/branches/1.8

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  r335064 | mjordan | 2011-09-09 11:09:09 -0500 (Fri, 09 Sep 2011) | 23 lines

  Updated SIP 484 handling; added Incomplete control frame

  When a SIP phone uses the dial application and receives a 484 Address
  Incomplete response, if overlapped dialing is enabled for SIP, then
  the 484 Address Incomplete is forwarded back to the SIP phone and the
  HANGUPCAUSE channel variable is set to 28.  Previously, the Incomplete
  application dialplan logic was automatically triggered; now, explicit
  dialplan usage of the application is required.

  Additionally, this patch adds a new AST_CONTOL_FRAME type called
  AST_CONTROL_INCOMPLETE.  If a channel driver receives this control frame,
  it is an indication that the dialplan expects more digits back from the
  device.  If the device supports overlap dialing it should attempt to
  notify the device that the dialplan is waiting for more digits; otherwise,
  it can handle the frame in a manner appropriate to the channel driver.

  (closes issue ASTERISK-17288)
  Reported by: Mikael Carlsson
  Tested by: Matthew Jordan

  Review: https://reviewboard.asterisk.org/r/1416/
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git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/10@335078 65c4cc65-6c06-0410-ace0-fbb531ad65f3