Updated openstack/openstack
Project: openstack/heat  eb15010e49f579ac30dbca2e54acdb3a6c008b00
null
Update tox.ini to use new features

tox 1.6 allows us to skip the sdist step, which is slow. This does that.
It also allows us to override the install line. In this case, it's
important as it allows us to stop getting pre-release software we
weren't asking for.

Original patch by Monty Taylor, talked about here:
http://lists.openstack.org/pipermail/openstack-dev/2013-September/015495.html

Change-Id: I9fe8a6cff149b3b79d434dc955c77a358c43031d