Verify that all EC2 resources are cleaned up after termination

[mikewalch]

Muchos should clean up any EC2 resources (i.e volumes or security groups #6) after termination of the EC2 cluster.

[codebyneesh]

I am working on this issue.

[ctubbsii]

I'd expect volumes to be configured to delete_on_terminate when their corresponding instances are deleted, but if volumes are created and attached separately from the instance, then that would be an exception. I don't know if that's the case.