Record instance actions and events

Record when an action is initiated on an instance, and the underlying
events related to completing that action.

Actions will typically occur at the API level and should match what a
user intended to do with an instance.  Events will typically track what
happens behind the scenes and may include things that would be unclear
for a user if exposed, but should be beneficial to an admin/deployer.

Adds a new wrapper to the compute manager, and some utilities to aid in
wrapping.  The wrapper will record when an event begins and finishes
from the point of view of the compute manager.  It will also record
errors if they occur.

Blueprint instance-actions

Change-Id: I801f3e796d091e146413f84c2ccfab95ad2e1af4