Only updating python-mysql if we aren't on jenkins

At 30 minutes we still hit it sometimes when building from a bare ubuntu box.

New AMI, old one busted

Defaulting it to hammer for now.

The test_build_server role was failing on acceptance tests because of unicode
static assets being gathered in collectstatic for django. This was because of
this issue https://github.com/ansible/ansible/issues/6655, which has been
resolved in recent ansible versions. We must override the version that is
being used by this repo, and upgrade ansible at provisioning time for
running the test_build_server role.

Also disables lettuce verification on test_build_server role.