implement model changes

- add new domains.apps.AppConfig to allow translatable app description for
  domains app
- link domains to a customer
- extract common functionality from domains.models.MailDomain into abstract
  domains.models.DomainBase
- add separate domains.models.HostingDomain to allow for generic external
  domains
- add new hostingpackages.models.CustomerHostingPackageDomain to assign hosting
  domains to hosting packages

gnuviechadmin/hostingpackages/models.py

@@ -14,6 +14,7 @@ from django.utils.translation import ugettext_lazy as _, ungettext
 from model_utils import Choices
 from model_utils.models import TimeStampedModel
 
+from domains.models import HostingDomain
 from managemails.models import Mailbox
 from osusers.models import (
     AdditionalGroup,
@@ -66,6 +67,7 @@ class HostingOption(TimeStampedModel):
 
     """
 
+
 @python_2_unicode_compatible
 class DiskSpaceOptionBase(models.Model):
     diskspace = models.PositiveIntegerField(_('disk space'))
@@ -83,6 +85,7 @@ class DiskSpaceOptionBase(models.Model):
         return _("Additional disk space {space} {unit}").format(
             space=self.diskspace, unit=self.get_diskspace_unit_display())
 
+
 class DiskSpaceOption(DiskSpaceOptionBase, HostingOption):
     """
     This is a class for hosting options adding additional disk space to
@@ -329,6 +332,30 @@ class CustomerHostingPackage(HostingPackageBase):
         return super(CustomerHostingPackage, self).save(*args, **kwargs)
 
 
+@python_2_unicode_compatible
+class CustomerHostingPackageDomain(TimeStampedModel):
+    """
+    This class defines the relationship from a hosting package to a hosting
+    domain.
+
+    """
+    hosting_package = models.ForeignKey(
+        CustomerHostingPackage, verbose_name=_('hosting package'),
+        related_name='domains')
+    domain = models.OneToOneField(
+        HostingDomain, verbose_name=_('hosting domain'))
+
+    def __str__(self):
+        return self.domain.domain
+
+    def is_usable_for_email(self):
+        """
+        Tells wether the related domain is usable for email addresses.
+
+        """
+        return self.domain.maildomain is not None
+
+
 class CustomerHostingPackageOption(TimeStampedModel):
     """
     This class defines options for customer hosting packages.