Exclude heartbeat timestamp from agent list checks

Do not compare the heartbeat timestamp in comparisons for
agent list test as updates from agents might update it
and cause the test to fail.

Change-Id: Ia90ebb96bd005d36f519a2ec88bd0277922048c8
Closes-Bug: #1261814
Add volume cleanup to test_volume_transfer test

The tempest tests were leaving volumes behind when it
finished up.  Turns out these were from the test_volume_transfer
tests.

The normal delete/cleanup methods can't be used here because we do
the whole bit of transferring the ownership of the volume so the base
client isn't the one that ends up having access to the volume.

This patch adds a delete and wait for cleanup method that's called
by the addition of an addCleanup task.

Change-Id: I6d27c7748ae386d97e727ddf0f8bb94046e6e88d
Closes-Bug: 1272533
Merge "Add volume cleanup to test_volume_transfer test"
Merge "Exclude heartbeat timestamp from agent list checks"