Tweak bishop PSQT tables

Tuned after 49K iterations of SPSA.

Passed both short TC:
LLR: 2.97 (-2.94,2.94) [-1.50,4.50]
Total: 14231 W: 2684 L: 2542 D: 9005

And long TC:
LLR: 2.94 (-2.94,2.94) [0.00,4.00]
Total: 87556 W: 13757 L: 13342 D: 60457

bench: 6875743
Merge pull request #9 from mcostalba/master

Updating master