Create teensySNES_test3.ino

Changed Button Debug to enable LED with ANY key press.  Added some extra debug points (commented out by default). 
Made accelerometer mouse movement calculations trigonometric (adjust input to tan(±65°))
Adjusted accelerometer values to work better with new formula using ADXL335 BBoard v2.
  To adjust for different samples uncomment serial debugging and comment out Mouse.move command (line 195)