修改账户系统以及部分用户权限写法

增加部分测试和注释，完善国际化

account/middleware.py

@@ -2,20 +2,23 @@
 import time
 import json
 import urllib
+
 from django.http import HttpResponseRedirect, HttpResponse
+from django.utils.translation import ugettext as _
 from django.contrib import auth
-from .models import ADMIN
+
+from .models import AdminType
 
 
 class SessionSecurityMiddleware(object):
     def process_request(self, request):
-        if request.user.is_authenticated() and request.user.admin_type >= ADMIN:
+        if request.user.is_authenticated() and request.user.admin_type in [AdminType.ADMIN, AdminType.SUPER_ADMIN]:
             if "last_activity" in request.session:
-                # 24个小时没有活动
+                # 24 hours passwd since last visit
                 if time.time() - request.session["last_activity"] >= 24 * 60 * 60:
                     auth.logout(request)
                     if request.is_ajax():
-                        return HttpResponse(json.dumps({"code": 1, "data": u"请先登录"}),
+                        return HttpResponse(json.dumps({"code": 1, "data": _("Please login in first")}),
                                             content_type="application/json")
                     else:
                         return HttpResponseRedirect("/login/?__from=" + urllib.quote(request.path))