ai bug
fix bug in validPosition that always return True
solve the problem of click out of bound object
slow down water a little bit
readme typo
test push
sync ai state among client
comment templet code
add player in/add block/ player out info;
fix mutil player bug that reward not remove for new player
AI fatal bug fixed, optimized,time and memory cost, add heristic score to evaluate all the reward for AI
Merge branch 'lucas' of https://github.com/yutongp/RaiseMeUp into ypei

Conflicts:
	client/code/app/game_client.js
improve instruction clearity