Use Django's builtin reverse_lazy

mayan/apps/main/api.py

@@ -1,12 +1,9 @@
 from __future__ import unicode_literals
 
-from django.core.urlresolvers import reverse
-from django.utils.functional import lazy
+from django.core.urlresolvers import reverse_lazy
 
 diagnostics = {}
 tools = {}
-# TODO: Use Django's included reverse_lazy
-reverse_lazy = lazy(reverse, str)
 
 
 def register_maintenance_links(links, title=None, namespace=None):