Simplify pawnless endgame evaluation

Retire KmmKm evaluation function. Instead give a very drawish
scale factor when the material advantage is small and not much
material remains.

Retire NoPawnsSF array. Pawnless endgames without a bishop will
now be scored higher. Pawnless endgames with a bishop pair will
be scored lower. The effect of this is hopefully small.

Consistent results both at short TC (fixed games):
ELO: -0.00 +-2.1 (95%) LOS: 50.0%
Total: 40000 W: 7405 L: 7405 D: 25190

And long TC (fixed games):
ELO: 0.77 +-1.9 (95%) LOS: 78.7%
Total: 39690 W: 6179 L: 6091 D: 27420

bench: 7213723
Tweak knight PSQT tables

Passed both short TC:
LLR: 2.97 (-2.94,2.94) [-1.50,4.50]
Total: 31765 W: 6103 L: 5913 D: 19749

And long TC:
LLR: 2.96 (-2.94,2.94) [0.00,6.00]
Total: 38867 W: 6268 L: 5988 D: 26611

bench: 7804908
Increase max hash size to 16GB

TCEC season 3, which is due to start in a few weeks, just
had its server upgraded to 64GB RAM and will therefore allow
16GB hash to be used per engine.

This is almost the upper limit without changing the
type of size and hashMask. After this we need to
move to uint64_t instead of uint32_t.

No functional change.
Fix +M0 score when low on time

When time remaining is less than Emergency Move Time,
we won't even complete one iteration and engine reports
a stale +M0 score.

To reproduce run "go wtime 10"

info depth 1 seldepth 1 score mate 0 upperbound nodes 2 nps 500 time 4 multipv 1 pv a2a3
info nodes 2 time 4
bestmove a2a3 ponder (none)

This patch fixes the issue.

Tested by Binky at very short TC: 0.05+0.05
ELO: 5.96 +-12.9 (95%) LOS: 81.7%
Total: 1458 W: 394 L: 369 D: 695

And at a bit longer TC:
ELO: 1.56 +-3.7 (95%) LOS: 79.8%
Total: 16511 W: 3983 L: 3909 D: 8619

bench: 7804908
Small simplification to Position::see

Verified there are no hidden bugs and is
actually a speed optimization:

Fixed games at 15+0.05 TC
ELO: 1.72 +-2.9 (95%) LOS: 87.5%
Total: 20000 W: 3741 L: 3642 D: 12617

No functional change
Do not set default value for architeture in Makefile

Fixes a regression that ARCH parameter was not properly validated.
Invalid value would default to generic 32-bit build.

No functional change.
Variable null-move value based reduction

Instead of a fixed reduction of ONE_PLY, now
Null move dynamic reduction based on value can
grow larger in case we are above beta of a value
much higher then PawnValueMg.

Note that now an eval returning VALUE_KNOWN_WIN
makes null search to drop in qsearch.

Passed both short TC:
LLR: 2.95 (-2.94,2.94) [-1.50,4.50]
Total: 26141 W: 4871 L: 4699 D: 16571

And long TC:
LLR: 2.97 (-2.94,2.94) [0.00,6.00]
Total: 33695 W: 5309 L: 5056 D: 23330

bench: 7356053