Permit callee to continue in the dialplan, after caller has hung up.

(closes issue #11954)
 Reported by: johan
 Patches: 
       app_dial_rev104031.patch uploaded by johan (license 334)


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@113649 65c4cc65-6c06-0410-ace0-fbb531ad65f3