More automated tests

[bitwalker]

The current test suite runs a rather simplistic test, but a decent one:

• Starts two nodes
• Connects them together
• Starts Swarm on both
• Creates 50 worker processes
• Disconnects the two nodes, simulating a network partition
• Checks to see that all 50 procs are registered properly on both sides of the partition
• Joins the partitions
• Checks to see that there are only 50 procs in the cluster, and that they are back on the nodes where they belong, and that the registry on both nodes is correct

Tests needed:

• [x] Basic test as described above
• [ ] The same as the above, but adds/removes registrations from both sides of the partition and then ensures that the conflicts are correctly resolved
• [ ] Same as the above 2, but with 3 nodes, make sure they agree
• [ ] Tests with many short-lived processes, say create 100 processes which exit after 1s to create churn in the tracker, and ensure it does the right thing.
• [ ] Test the original scenario, but brutally kill one of the nodes so that it doesn't have a chance to shut down gracefully.