Add Bumper Support

[Starsurfer78]

If i read the README right, they are no Bumpers yet. It would be nice if you can add it 2 Pins for it. Perhaps
Micro Switch or Hall Sensors.

[Selective031]

No bumber support yet, I wrote some code a while back which I later removed because the motor spike was very good. But of course there should be bumber support.

[MagnusPer]

Could not a ultrasonic sensor do the work? One example could be the DYP-A02YYUltrasonic Waterproof Distance Sensor

[Starsurfer78]

Yes but if the Ultrasonic didn't see the Obstacle then the bumper is a safety device