[rvcnedou] Crazyhouse Annihilation move generator

A move generator for the chess variant Crazyhouse Annihilation.

Moves are chosen randomly, except if there is an opportunity to capture the opponent's last piece ("mate in one"), in which case, that move is made, and the game ends. A long simulation (124 trials) yields a mean of 36,398,738.7 half-moves with sample standard deviation 36836794.1. The mean and standard deviation are about equal, in agreement with an exponential distribution. Dividing by sqrt(124), the estimate for the mean is 36.4 million plus or minus 3.3 million half-moves; rather long random games.

7630452 22717328 1600136 14015459 21539011 13711924 48283546 5772193 16319645 37093047 79503837 54435215 110070860 24644899 22004497 12207972 675804 5947667 26349370 9512429 7573088 33595376 2289329 9662882 19753271 80149142 21961820 25278477 68228879 44236144 99503035 41034528 22904729 32346612 27838745 17019677 143714531 46624081 2855386 30205296 24293125 6675240 16438392 7629971 17827856 9960190 7754548 282138 24260669 32352649 41418611 24009095 58304490 27922544 25364224 14735447 50075532 42742386 2186122 103677503 103132932 34411040 44442236 42321348 13827557 68990002 161009323 25228401 44199181 53381106 60350344 20533842 39253957 5079703 32182670 43574038 4003573 51512099 14903701 21293651 29660311 36340996 30362821 50369123 85979494 41646307 5481770 2450843 71982027 37825804 7794606 10607661 204793965 47677483 52374165 33805511 34430147 21912834 18499443 7269401 48240436 25676985 27901021 11779196 2467145 118250105 16245725 41248864 6325937 48154665 48486272 10496841 196964767 113587480 17017582 1369183 29655663 10898873 14683696 88292737 5798507 18781484 13043640 34460332