Revision 739628

python: Make the unit tests run faster and more reliably

- The async test was making the server sleep for 2 seconds.  Cut it to 0.5.
- The test driver was waiting 5 seconds for shutdown.  Cut it to 1.
- Add a 0.25 second sleep to make sure the server comes up before the client.

This is all a bit hacky, but it is better than the status quo.