Merge pull request #51 from winstonho/master

update
Merge pull request #52 from lyDASHsBOK/master

update
Merge pull request #21 from lyDASHsBOK/master

merge
Merge pull request #22 from lyDASHsBOK/master

updated stretcher
Merge pull request #53 from lyDASHsBOK/master

update
Merge pull request #23 from lyDASHsBOK/master

updated stretcher
splashScreen and Preload fix
Merge pull request #54 from winstonho/master

update
update
Merge pull request #24 from huanzhz/master

m
AI movement
Merge pull request #55 from winstonho/master

update
update
Merge pull request #25 from huanzhz/master

m fireball
fireball collsion done
Merge pull request #56 from winstonho/master

update
position fix of ai
Merge pull request #57 from winstonho/master

position fix of ai
update
Merge pull request #26 from huanzhz/master

m