Updated from 2011 patch by fjakobs:
36ebe6c496
* removes old double-width CJK handling
* replaces monospace assumptions with measurements of actual text
* appears to work for Latin, CJK, Thai, Malayalam in ad-hoc testing
* does NOT fully handle RTL text issues (Hebrew, Arabic)
Conflicts:
demo/kitchen-sink/doclist.js
lib/ace/edit_session.js
lib/ace/layer/text.js
lib/ace/virtual_renderer.js
bcba9bea6e