0.2.0: Add integration testing subcommand which monitors new nodes for successful updates

[cbgbt]

Issue or Feature Request:
The integration subcrate is currently written to manually assemble a cluster that can allow a human to quickly verify that nodes are being updated using kubectl get brn.

One way we could expand this into a pass/fail test mechanism would be to create a subcommand of the integration test subcrate (or a script) which provides userdata to the launched instances to lock to a particular target version for updates, then use an AMI of an older version of Brupop. After waiting some amount of time, we could confirm that the instances successfully made it to the target version and the Idle state.