Merge pull request #178 from paltman/master

Fix deprecation warning in Django 1.8

sitetree/utils.py

@@ -1,9 +1,13 @@
 from django.contrib.auth.models import Permission
 from django.core.exceptions import ImproperlyConfigured
 from django.utils import six
-from django.utils.importlib import import_module
 from django.utils.module_loading import module_has_submodule
 
+try:
+    from importlib import import_module
+except ImportError:  # Python < 2.7
+    from django.utils.importlib import import_module
+
 try:
     from django.apps import apps
     apps_get_model = apps.get_model