Patched CallbackHelpers to allow callback with empty command

- incremented version to 0.3.2
- current spec status: 576 examples, 0 failures
Updated ProxyController, CallbackController to play nice with empty action

- incremented version to 0.3.3
- current spec status: 580 examples, 0 failures
Updated ProxyController again for empty actions

- incremented version to 0.3.4
- current spec status: 584 examples, 0 failures