This module has not been built in years, since the (removed) esp8266 port.
Delete the code, as it is not likely to be useful in its current form.
Closes: #7015
Everything should be using the keypad module instead.
Note: there are several boards that still had gamepadshift enabled. I
did not contact their authors to make sure they already switched to
keypad in their code and documentation. We should probably wait with
merging this for their go ahead.
Dan Halbert
Radomir Dopieralski
Dan Halbert
Jeff Epler
Kenny
Scott Shawcroft
Kattni Rembor