fix for arrow keys being reversed in the snap menu (Ctrl+Shift+Tab)
also - when expanding rna enums into existing menus - don't nest inside a row/column.


git-svn-id: https://svn.blender.org/svnroot/bf-blender/trunk/blender@53867 954f8c5b-7b00-dc11-b283-0030488c597c