Ensure tempest writes a full manifest

The tempest element uses pip install after generating the manifest,
meaning that it installs software not listed in its manifest.

Fix it so that it writes the manifest after the last of these
installs.

Change-Id: I456d650c0bcba448cb18efad95e7daeccd5d9e0b
Add DEPLOYMENT_MODE to local_settings.py

DEPLOYMENT_MODE determine if we do flavor matching, it can be "poc" (No) or "scale" (Yes).
This is used in Tuskar-ui to show flavor administration options etc.

Change-Id: I6a1b1cbb9cfe8d2750023d6ea633cf3390468c43
Merge "Add DEPLOYMENT_MODE to local_settings.py"
Merge "Ensure tempest writes a full manifest"