Apply font configuration from GConf (#1584)

Sugar font settings are now stored in GConf. This patch applies them
to all users of sugar.style and all standard activities.

src/sugar/activity/activity.py

@@ -280,6 +280,9 @@ class Activity(Window, gtk.Container):
         self._jobject = None
         self._read_file_called = False
 
+        settings = gtk.settings_get_default()
+        settings.set_property("gtk-font-name", "%s %f" % (style.FONT_FACE, style.FONT_SIZE))
+
         self._session = _get_session()
         self._session.register(self)
         self._session.connect('quit-requested',