fix for horizon/devstack issue
fix for horizon/devstack issue

As of pip 8.x installing from external links is not allowed when
constraints are enforced, this is causing cue-dashboard
installation to fail because cue-dashboard is pulling in
horizon as an external link as part of test-requirements.

Since test requirements won't be needed during devstack gate
testing, cue-dashboard/test-requirements.txt is being shuffled
around to avoid installing cue-dashboard/test-requirements.  This
follows the approach that Manila uses in
I841b56f65b50e9c5673cc02e93b4329ed29125ba

Change-Id: I29524df86146762aac5430efafaf7a02b705f539

stackforge/cue,openstack/cue,openstack/cue,stackforge/cue,openstack/cue,stackforge/cue