[gnome-tweak-tool] Require g-i Gtk version 3.0

[John Stowers <jstowers src gnome org>]

commit 273226d6cdc9d0fc1861fbec62b0fedaf3318015
Author: John Stowers <john stowers gmail com>
Date:   Fri Mar 18 10:40:50 2011 +1300

    Require g-i Gtk version 3.0

 gnome-tweak-tool |    3 +++
 1 files changed, 3 insertions(+), 0 deletions(-)
---
diff --git a/gnome-tweak-tool b/gnome-tweak-tool
index 28e41fe..ebfd1a7 100755
--- a/gnome-tweak-tool
+++ b/gnome-tweak-tool
@@ -3,6 +3,9 @@
 import os.path
 import optparse
 
+import gi
+gi.require_version("Gtk", "3.0")
+
 from gi.repository import Gtk
 
 import gtweak