Add Uniqueid header to ParkedCall manager event.

(closes issue #13323)
Reported by: srt
Patches:
      13323_unique_id_for_parkedcalls_event.diff uploaded by srt (license 378)


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@138479 65c4cc65-6c06-0410-ace0-fbb531ad65f3