[fix bug 1226779] Upgrade django to version 1.7.11.
[fix bug 1226779] Upgrade django to version 1.7.11.

brian-yang/mozillians,anistark/mozillians,akatsoulas/mozillians,anistark/mozillians,akatsoulas/mozillians,johngian/mozillians,fxa90id/mozillians,fxa90id/mozillians,anistark/mozillians,johngian/mozillians,mozilla/mozillians,johngian/mozillians,brian-yang/mozillians,mozilla/mozillians,fxa90id/mozillians,fxa90id/mozillians,akatsoulas/mozillians,mozilla/mozillians,mozilla/mozillians,brian-yang/mozillians,akatsoulas/mozillians,johngian/mozillians,brian-yang/mozillians,anistark/mozillians