Fix [#37077] User prefs > Input and Outliner Keymaps mismatch in representation.

Remove KeyMap mode from outliner, was an old half-finished features redondant with user preferences settings...

Also moved key map item's "event type to map type" and map type defines at WM level, this is too much generic to be at RNA level.

Also added a check in versionning code to convert all outdated outliner modes to a valid one (seems old 'verse' ones were not handled as well).

Thanks to Brecht for reviews and advices!

git-svn-id: https://svn.blender.org/svnroot/bf-blender/trunk@60775 954f8c5b-7b00-dc11-b283-0030488c597c