Allow single akephalos instance to have multiple connections

[bernerdschaefer]

Rather than serving a single instance of Akephalos::Client over DRb, you should be able to have multiple clients connect to the server and run simultaneously. This would allow a few things:

1. Start a single, long-running server instead of starting and stopping the server for each test run.
2. Allow tools like hydra and specjour which run multiple workers on a single box to talk to the same server.

[mcmire]

This would be appreciated, simply for the first case. I do so hate the slow startup time :(