VMWare - Check for compute node before triggering destroy

While booting an instance, if Claim on that compute node is not successful
compute manager triggers a call to destroy instance. Destroy fails since the
compute node (Cluster/ESX host) is set only after claim is successful.
Hence the check for node is made before destroy, to ensure that exception
does not get thrown. This ensures that the instance gets rescheduled
Closes-Bug: #1307408

Change-Id: Iaaf931e9c1e6cf046497e2c64952f92e802ad4be
(cherry picked from commit aadfffaaa69c6a8939f6c88cfbaeb026c7604163)
Add info_cache as expected attribute when evacuate instance

Nova evacuates instance failed with neutron. The reason is
when nova-conductor try to get network info for instance, it
need instance include 'info_cache', but the instance dict which
passed didn't include it. This patch adds 'info_cache' as the
expected attribute for get instance.

Change-Id: I6f110c607e32b0ab536916741605b25d572331dc
Closes-Bug: #1284709
(cherry picked from commit 4c68f19cd8d1f045bde02be7eec50c34c1d87932)
Merge "Add info_cache as expected attribute when evacuate instance" into stable/icehouse
Merge "VMWare - Check for compute node before triggering destroy" into stable/icehouse