Update to purejavacomm-0.0.17

I had some trouble with serial communications over Bluetooth
that I hoped should be solved with this update, but it didn't.
But lets use the latest and greatest anyway.
Added code and new commands to report user keyboard interactions

* Detecting keypresses on the keyboard by measuring length
  of the measurement.
* Reset the button mask when user interracts with keyboard to
  avoid problems.

Totally untested.