rhbz978666 - prove of concept works
rhbz978666 - enable add comment in history view
rhbz978666 - bring back copy into editor function
rhbz978666 - bring back compare
rhbz978666 - retrofit test
rhbz978666 - change span to anchor
rhbz978666 - remove old implementation
rhbz978666 - apply new style
rhbz978666 - localize some strings and some styles change
add javadoc
delete unused classes