Update the permissions tag to the new class based permissions

apps/permissions/templatetags/permission_tags.py

@@ -2,7 +2,7 @@ from django.core.exceptions import PermissionDenied
 from django.template import TemplateSyntaxError, Library, \
                             Node, Variable
 
-from permissions.api import check_permissions as check_permission_function
+from permissions.models import Permission
 
 register = Library()
 
@@ -21,7 +21,7 @@ class CheckPermissionsNode(Node):
             return u''
         requester = Variable(self.requester).resolve(context)
         try:
-            check_permission_function(requester, permission_list)
+            Permission.objects.check_permissions(requester, permission_list)
             context[u'permission'] = True
             return u''
         except PermissionDenied: