CommCare HQ no longer runs on python 2.6; upgrade to python 2.7

Dear developers,

I wanted to announce that as this
two weeks ago, the commcare-hq project no longer supports python 2.6.
Therefore if you run a CommCare HQ server that runs python 2.6, you will
have to upgrade your machines to use python 2.7. We apologize for any
inconvenience in the late notice.