use django MiddlewareMixin to support new style Middleware

hijack/middleware.py

@@ -1,6 +1,12 @@
 # -*- coding: utf-8 -*-
+try:
+    from django.utils.deprecation import MiddlewareMixin
+except ImportError:
+    class MiddlewareMixin(object):
+        pass
 
-class HijackRemoteUserMiddleware(object):
+
+class HijackRemoteUserMiddleware(MiddlewareMixin):
     """
     Middleware for hijack RemoteUser. One must place this middleware between
     'django.contrib.auth.middleware.AuthenticationMiddleware' and

hijack/tests/test_settings.py

@@ -42,6 +42,7 @@
     'django.contrib.auth.middleware.AuthenticationMiddleware',
     'django.contrib.messages.middleware.MessageMiddleware',
     'django.middleware.clickjacking.XFrameOptionsMiddleware',
+    'hijack.middleware.HijackRemoteUserMiddleware',
 )
 
 MIDDLEWARE_CLASSES = MIDDLEWARE