Partial revert of own commits r56604 and r56603:
* Reverted the changes to code comments, as suggested by Campbell. It makes it more hard to follow.
* Only keep changes to actual UI messages. 

git-svn-id: https://svn.blender.org/svnroot/bf-blender/trunk/blender@56612 954f8c5b-7b00-dc11-b283-0030488c597c