Add EnemySwatInitializer
Add EnemySwatInitializer
Initialize EnemySprite with swat sequence
Add SwatShootCommand
add swatSprite and swatShootTimer as a new entry to SwatTimerTable
Cancel shoot timer when swat is dead
add bullet.png and imagesheet data
add bullet to SpriteSequenceData
create bullet when SwatShootCommand execut
set velocity to bullet
Fixed fail tests
Add BulletHisPlayerListener as an collision event listener of bullets
Add BulletHitPlayerListener
Remove bullet when hit the player sprite
Fixed calling removeSelf in BulletHitPlayerListener