prepare readme for sf 5 js release

Merge tag 'sf_dd'

Conflicts:
	src/uci.cpp

Stockfish 4

Stockfish bench signature is: 4132374

Stockfish 3

Stockfish bench signature is: 4176431

Disable "Use Sleeping Threads"

Print leading zeroes in hash keys

And convert to uppercase. Reset the stream to dec too.

[Edit: Also fixed the hash key in Position::pretty()]

+5 ELO after 14K on Balint

vs base

Restore "fail-low of reduced" and close regression

This reverts "Threat Extensions" and is the last of
this revert series.

In single-thread tests we should now be on par with 2.3.1

Simplify evaluation