ACL2: implement build-next-generation and avl-tree->output-lines
ACL2: implement build-next-generation and avl-tree->output-lines

It still needs work to read from standard input and write HTML as output.

grantbacon/conways-game-of-life-service,grantbacon/conways-game-of-life-service,grantbacon/conways-game-of-life-service