System specification

Initial README with system specification from the system design discussion, #4.
@arschles Ok, I will include some, but here is some dimensions are width x height :

Mode : max 40
Original : 80 x 160
Output : 20 x 40

Mode : max_height 40
Original : 80 x 160
Output : 20 x 40

Mode : max_width 40
Original : 80 x 160
Output : 40 x 80