Replace assertEqual(None, *) with assertIsNone in tests

Replace assertEqual(None, *) with assertIsNone in tests to have
more clear messages in case of failure.

Change-Id: I442951deb2bc6df199a1dd76142f71fc92e6f745
Closes-Bug:#1280522
CLI support for NSX gateway devices

Related to blueprint nsx-remote-net-gw-integration

Change-Id: Iedd080a29e281355420ace955fb09d196b54a316
Updated from global requirements

Change-Id: I54601b68bdf8660990efa82cdd8c961e7aff990c
Merge "Replace assertEqual(None, *) with assertIsNone in tests"
Merge "Updated from global requirements"