Valve In-process Launcher for functional tests

The class we're using for most functional tests, ReposeValveLauncher, starts valve in a separate process. In contrast, the ReposeInProcessValveLauncher class allows us to start Valve in the same JVM as the tests. This is helpful for debugging the tests when running in the IDE. 

The new launcher is merely a useful help for now, and there is no near-term intention of using it to replace the other launcher in tests. This pull request includes some minor changes to Valve classes so that they don't require objects to hold command line arguments, which aren't needed if we're not starting valve from the command line.