Catch InstanceIsLocked exception on server actions

If the server is locked, server actions raise 409 error, and the error
message is like "Instance is in an invalid state for 'pause(action name)'". The
error message is inappropriate, two points:
1. the state is valid for pause
2. the message doesn't tell that the instance is locked

The patch fixes the problem, and will modify on v2 and v3.

Change-Id: I7e21037b9abca5a3fd0f64dd5621e88dcf1a3c21
Closes-Bug: #1256873
VMware: update test file names

The tests files names all had prefix vmwareapi. This is no longer
needed as the test files are now under the vmwareapi directory.

The patch also fixed the permission for the file test_vm_util.py.

Change-Id: I87955a0a4d4d2b2c1dd55203658707ce7c6038f0
Merge "VMware: update test file names"
Merge "Catch InstanceIsLocked exception on server actions"