Allow new quota types

On Nova commit Ib281e43eabfbd176454bde7f0622d46fb04fcb79, we are trying
a new quota type for server groups.
However, current Tempest denies unexpected quota types on its own tests,
and we cannot add the new quota without Tempest changes.
This patch changes quota tests for checking mandatory quota existence
and allowing new quota types.

Change-Id: I4409a7240dc0a3fa1e11c64c5f5a56ca656b70a4
Merge "Allow new quota types"