unicode: Update to Unicode 6.3.0 release

git-svn-id: svn://vcs.exim.org/pcre/code/trunk@1362 2f5784b3-3f2a-0410-8824-cb99058d5e15
Refactored auto-possessification code.


git-svn-id: svn://vcs.exim.org/pcre/code/trunk@1363 2f5784b3-3f2a-0410-8824-cb99058d5e15