Do not use relative import

Doesn't work well when running tests.

housing/apps.py

@@ -1,14 +1,12 @@
 # -*- coding: utf-8 -*-
-from __future__ import unicode_literals
 
+from __future__ import unicode_literals
 from django.apps import AppConfig
 import coin.apps
 
-from . import urls
-
 
 class HousingConfig(AppConfig, coin.apps.AppURLs):
     name = 'housing'
     verbose_name = "Gestion d'accès Housing"
 
-    exported_urlpatterns = [('housing', urls.urlpatterns)]
+    exported_urlpatterns = [('housing', 'housing.urls')]

vps/apps.py

@@ -1,14 +1,12 @@
 # -*- coding: utf-8 -*-
-from __future__ import unicode_literals
 
+from __future__ import unicode_literals
 from django.apps import AppConfig
 import coin.apps
 
-from . import urls
-
 
 class VPSConfig(AppConfig, coin.apps.AppURLs):
     name = 'vps'
     verbose_name = "Gestion d'accès VPS"
 
-    exported_urlpatterns = [('vps', urls.urlpatterns)]
+    exported_urlpatterns = [('vps', 'vps.urls')]