Put py34 first in the env order of tox
Put py34 first in the env order of tox

To solve the problem of "db type could
not be determined" on py34 we have to run py34 env before py27.
This patch puts py34 first on the tox.ini list of envs to avoid this
problem to happen.

Change-Id: I25d1bbd1abaafa4a443d36c9b68481891391ddf7
Closes-bug: #1489059

openstack/python-zaqarclient