fix b2g urls to force trailing slash

apps/b2g/urls.py

@@ -2,7 +2,7 @@ from django.conf.urls.defaults import *
 from views import b2g, about, faq
 
 urlpatterns = patterns('',
-    (r'^b2g/faq/', faq),
-    (r'^b2g/about/', about),
-    (r'^b2g/', b2g),
+    (r'^b2g/faq/$', faq),
+    (r'^b2g/about/$', about),
+    (r'^b2g/$', b2g),
 )