plotting matlab script

This script plots avg execution time vs depth (stacked bar graph. The
three partitions are the three thirds of the game) and execution time vs
turn number (with a median filter on to make it less noisy).

TODO:
- mess with the filter settings
- redo depth=12. The data seems off?
- Instead of just dividing the game into three equal parts, detect the
three phases of chess: opening, middlegame, and endgame