add member variable initialisation
Merge branch 'master' into fix_crash
uncomment code
uncomment laycolor
add glBindBuffer(GL_ARRAY_BUFFER, 0);
fix compile warning
Merge pull request #31 from dabingnn/fix_crash

Fix crash
Merge pull request #32 from fusijie/master

Fixed NotifationCenter bug && Add gameover control
Completed Gameover Stop all actions and Remove Enemys & Bullets