ENH: add more keyboard shortcuts in Editor

Per request from Sonia, give shortcuts for paint, draw, wand, and
rectangle effects.

See full list here:

http://wiki.slicer.org/slicerWiki/index.php/Documentation/Nightly/Modules/Editor#Editor_Wide_Keystrokes

Also STYLE: some dead code removal and end-of-line space removal.

git-svn-id: http://svn.slicer.org/Slicer4/trunk@21958 3bd1e089-480b-0410-8dfb-8563597acbee