Simplified urls file.

Below is brief description of changes:

1. Only `regex` pattern needs to be assigned inside `if` clause.
1. New order of assignments to `urlpatterns` makes it easier to understand and not to mess it accidentally.
1. There is no need to use `patterns` function to create `urlpatterns`. No `prefix` is used by `django CMS` and thus plain list is sufficient. By the way `patterns` function is depreciated in django 1.8 and will be removed in 2.0.