implement hosting domain creation

- implement domains.views.CreateHostingDomain
- define new URL create_hosting_domain in domains.urls
- add domains app URLs to gnuviechadmin.urls
- add templates domains/base.html and domains/hostingdomain_create.html
- link from hostingpackage detail page to domain creation view

gnuviechadmin/domains/urls.py

@@ -0,0 +1,16 @@
+"""
+This module defines the URL patterns for domain related views.
+
+"""
+from __future__ import absolute_import, unicode_literals
+
+from django.conf.urls import patterns, url
+
+from .views import CreateHostingDomain
+
+
+urlpatterns = patterns(
+    '',
+    url(r'^(?P<package>\d+)/create$', CreateHostingDomain.as_view(),
+        name='create_hosting_domain'),
+)