Major JIT compiler update. 

git-svn-id: svn://vcs.exim.org/pcre/code/trunk@1483 2f5784b3-3f2a-0410-8824-cb99058d5e15
Comment update.


git-svn-id: svn://vcs.exim.org/pcre/code/trunk@1484 2f5784b3-3f2a-0410-8824-cb99058d5e15