Multiple changes

[jhonnold]

Bench: 5115048

This patch merges many yellow patches + SPSA tuning.

• Additional continuation history for move picker ordering
• Adjust history ratios in move picker ordering
• Only accept beta cutoffs on cutnodes
• SPSA tune @ 12k iterations (60+0.6)
• More negative extensions
• LMR on captures on ttpv nodes
• QS futility values

ELO | 8.62 +- 4.56 (95%) SPRT | 40.0+0.40s Threads=1 Hash=64MB LLR | 2.95 (-2.94, 2.94) [0.00, 3.00] GAMES | N: 10160 W: 2444 L: 2192 D: 5524 http://chess.grantnet.us/test/33198/