Implement FINDLABEL matching for the new extension matching engine.

(closes issue #12800)
 Reported by: chris-mac
 Patches: 
       20080608__bug12800.diff.txt uploaded by Corydon76 (license 14)


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@121279 65c4cc65-6c06-0410-ace0-fbb531ad65f3