basic collision Detition
Merge pull request #44 from winstonho/master

basic collision Detition
update
Merge pull request #17 from huanzhz/master

m
update
Merge pull request #45 from winstonho/master

update
basic Collision
Merge pull request #46 from winstonho/master

basic Collision
jumping Collision Done
Merge pull request #47 from winstonho/master

jumping Collision Done
update
Merge pull request #18 from huanzhz/master

m2
more hill add
Merge pull request #32 from winstonho/master

 basic collision Detition