Increase Emergency Move Time to 20

Goes in the direction of avoiding time losses and seems
equivalent after almost 40K games at super fast TC of 10+0.05

ELO: 2.61 +-2.2 (95%) LOS: 99.1%
Total: 39869 W: 8258 L: 7959 D: 23652

No functional change.
Merge remote-tracking branch 'upstream/master' into king_def_B