Wall Following notes.

These are notes and ideas from the wall
following python program
 mainDec13.py

1) function spinRight() is never used.
2) a function   Motors(lspeed,rspeed)
   could be very useful.
it could:
   - stop the robot with Motors(0,0),
   - treat negative speeds as reverse,
   - accept non-integer speeds
   - limit speeds to be 0-65535
   - account for performance difference between the two motors
3) maybe a good idea to use LEDs to indicate which rurn/spin the robot is doing.

Coding improvements
a) put all numeric constants at the start.
  see line 211 "speed2= 45000"