implement create_mailbox functionality

- implement managemails.forms.CreateMailboxForm
- implement managemails.views.CreateMailbox
- add url pattern 'create_mailbox' to managemails.urls
- add templates managemails/base.html and managemails/mailbox_create.html
- add german translation
- add generated code documentation

gnuviechadmin/managemails/urls.py

@@ -0,0 +1,18 @@
+"""
+This module defines the URL patterns for mailbox and mail address related
+views.
+
+"""
+from __future__ import absolute_import, unicode_literals
+
+from django.conf.urls import patterns, url
+
+from .views import (
+    CreateMailbox,
+)
+
+urlpatterns = patterns(
+    '',
+    url(r'^(?P<package>\d+)/mailbox/create$',
+        CreateMailbox.as_view(), name='create_mailbox'),
+)