add list, delete and edit comment of SSH public keys

- add sshkeys to hostingpackage detail view context
- implement new osusers.forms.EditSshPublicKeyCommentForm
- implement new views ListSshPublicKeys, DeleteSshPublicKey and
  EditSshPublicKeyComment
- add new URL patterns 'list_ssh_keys', 'edit_ssh_key_comment' and
  'delete_ssh_key'
- link from hosting package detail view to 'list_ssh_keys' when there are
  SSH keys assigned to the shown hosting package
- add new templates osusers/sshpublickey_list.html,
  osusers/sshpublickey_confirm_delete.html and
  osusers/sshpublickey_edit_comment
- add operating system user output to template
  osusers/sshpublickey_create.html
- add changelog entry

gnuviechadmin/hostingpackages/views.py

@@ -121,6 +121,7 @@ class CustomerHostingPackageDetails(StaffOrSelfLoginRequiredMixin, DetailView):
             'domains': context['hostingpackage'].domains.all(),
             'mailboxes': context['hostingpackage'].mailboxes,
         })
+        context['sshkeys'] = context['osuser'].sshpublickey_set.all()
         return context