Also run it across the whole tree to get everything using the One True Style.
We don't yet run this in an automated fashion as it's a little slow, but
there is a snippet to do so in makeall.sh.
They show up as checkable GButtons in GToolBar, and with (or without) check
marks in menus.
There are a bunch of places to make use of this. This patch only takes
advantage of it in the FileManager for the view type actions.
The enabled state of a GAction now propagates both to any toolbar buttons
and any menu items linked to the action. Toolbar buttons are painted in
a grayed out style when disabled. Menu items are gray when disabled. :^)
