Swirl direction changes. Building "hard" and & "impossible" button on "menu" page.
Add three button in "menu" and delete "plane" from "menu".(Because of bad looking)
Change name "LEVEL2_STATE" to "PLAY_HARD_STATE", Change name "LEVEL3_STATE" to "PLAY_HARD_STATE".
Add "playHard" and "playImpossible" State
Comment "logo" from "asset.ts"
Scale XY for "plane.ts"
Fix "coin" "plane2" &"meteorolite2" size in "asset.ts"&"atlas.png"
Prepared "Bullet_enemy", begin to build enemy bullet in "BulletManager"&"play.ts"
Merge pull request #2 from BladeWork/master

Merge Code changes from Renfa Feng