Optimize the update_realtime_member_field function by not having

to query the database for the member and instead using a cached
uniqueid. 

Special thanks to atis for creating this and for keeping it up
to date with necessary changes

(closes issue #11896)
Reported by: atis
Patches:
      realtime_uniqueid_v6.patch uploaded by atis (license 242)
Tested by: atis



git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@117517 65c4cc65-6c06-0410-ace0-fbb531ad65f3