Use keyring for testing

Mention keyring in test-requires as in python-keystoneclient.
So, keyring support is enabled in shell.py and tested.

Change-Id: Icb712a07b995b47b286ed0528e04ae1d5ec195d2
Removes tenant IDs checking for nova quota operations.

Until there is a way to validate tenant IDs, remove the existing checks.

Fixes bug #1154582

Change-Id: If10fac17b919190c1492cfbf1be9950284a82197
Merge "Use keyring for testing"