Remove havana compat from nova.consoleauth.rpcapi

Since we only support upgrading from N-1 to N, there's no need to keep
around this older upgrade related code.

Change-Id: I253db2fe161add62cb248665c7920126f0d7455f
Refactor more compute tests to use Instance objects

Change-Id: If501760085a2110fedb8bd5e2fd863af25bc6f8e
Compute: improve usage of Xen driver support

Commit 69564763960cddc249138469811a0a771db16e19 added a check,
which was called twice, in get_next_device_name.

This is called once now.

Change-Id: I45c918bc64ed8049179fc01a7cd3ad81e4682fe1
Compute: improve test_compute_utils time

Make use test.NoDBTestCase instead of test.TestCase. This improves
the test times.

The tests that have been update do not use the DB.

Change-Id: I2a39f635552175117609dbbe6b328ead166345ea
Merge "Refactor more compute tests to use Instance objects"
Merge "Compute: improve usage of Xen driver support"
Merge "Remove havana compat from nova.consoleauth.rpcapi"
Merge "Compute: improve test_compute_utils time"