[FEAT] Add aunchpad pro

[airone01]

Hi, I'm Erwann, just an IT student.

I happen to own a Launchpad Pro (1st gen) and am willing to contribute.
I'm going to fork the repo and fiddle with it, as I need the Pro support anyways, but if you want I could make a PR.

See you around.

[kangalio]

Great! Yeah, feel free to fiddle with it, make it light up a little. If you end up improving this library in the process, a PR would be very nice