Fixed START, GOAL state#159

MichaelQiYinChen wants to merge 2 commits intoShangtongZhang:masterShangtongZhang/reinforcement-learning-an-introduction:masterfrom

MichaelQiYinChen:cliffwalking_fixMichaelQiYinChen/reinforcement-learning-an-introduction:cliffwalking_fixCopy head branch name to clipboard