Update jcommander-inject to use the more modern JCommander API

Update JCommander-inject's guice module builder to 
  - clarify the FluentAPI a bit
  - add an optional prefix to the qualified binding (i.e. "cli.")
  - add automatic binding of the concrete parameter holder types
  - update the docs and examples
  - split out the tests into mildly more robust cases.
  - support the more modern JCommander internals.