Launchkey MK3 DAW/MIDI integration

Hello Ardour community.

Retailers are moving old MK3 inventory at a good price so I got a 37 key unit recently.

It turns out that a naive integration into Ardour is not too difficult. I simply copied the directory libs/surfaces/launchpad_4 to libs/surfaces/launchpad_3 and make lite edits.

The edits were make on the 8.10 tag.

How should I share this back for better coverage of other MK3 devices?

a pull request on github is the easiest way. Or email an appropriate patch to help@ardour.org.