Editor: Use multi-caret editing to support renaming a start-tag and matching end-tag name simultaneously.
Ref http://bugs.activestate.com/show_bug.cgi?id=99446

(integrated from komodo (trunk) change 80834 by ericp)

git-svn-id: https://svn.openkomodo.com/repos/openkomodo/trunk@13237 b87d16e7-d29f-4ee1-b5ec-817d645d335f