Always use fakes_v1_1 for heat.tests.v1_1 fakes import

In some places there is import fakes from heat.tests.v1_1
as fakes_v1_1 and it's necessary because of importing
heat.tests.fakes. This patch makes all tests use 'fakes_v1_1'
for this import.

Change-Id: Ic20b4b0c1d66c088cb023585323404fe16b00097
Unit test for resource attribute SHOW fix

The change https://review.openstack.org/#/c/140766 was merged before a
previous version of this patch (for bug 1400557), but didn't have any
unit tests.  I've removed the fix but left the unit test here.

Closes-Bug: #1401107
Change-Id: I788c181ce55f076243f9bbdf791289a5f45c3758
Allow VolumeAttachments to delete in parallel

Deleting a VolumeAttachment was still blocking; this change allows other
resources to be processed while we are waiting for the volume to be
detached.

Change-Id: Id1a7bf2a353cb1f255ab335ab8c39edbeb4dc292
Merge "Unit test for resource attribute SHOW fix"
Merge "Always use fakes_v1_1 for heat.tests.v1_1 fakes import"
Merge "Allow VolumeAttachments to delete in parallel"