Depend on GTK+ 3.13.2

For RTL icon theme support
Rely on RTL icon theme support
Fix the name of the Preferences dialog
Link the undo/redo buttons
trivial: code style fix
Improve clock label
Updated Lithuanian translation
Do not create new fundamental types
Rename gschema file

It's a little mean to reset user settings, but only a little, and I
dislike this redundant schema name more than I should. Mahjongg and
Chess were the only games with redundant names (besides Sudoku, which is
losing all of its previous settings anyway), so now there are none.

Also, fix gettext domain
Updated Spanish translation
Updated smooth tileset from Jim Evins

https://bugzilla.gnome.org/show_bug.cgi?id=732452
Don't show HeaderBar / app menu on systems that don't support it

https://bugzilla.gnome.org/show_bug.cgi?id=732658
doap: replace Jason with myself
Updated Russian translation
Updated Russian translation
Update POTFILES.skip
Revert "Don't show HeaderBar / app menu on systems that don't support it"

This reverts commit 400d130c8a32be20628c2ac2eba4ddcf18772136.

Pushed accidentally; better patch is upcoming
Don't show HeaderBar / app menu on systems that don't support it
Updated Spanish translation
Updated Greek translation