fixed no effect with stopping tween between two frames
Merge branch 'v3' of https://github.com/cocos2d/cocos2d-x into v3
change tab to 4 space
change tab to 4 space
Merge branch 'v3' of https://github.com/cocos2d/cocos2d-x into v3
Merge branch 'v3' of https://github.com/2youyouo2/cocos2d-x into v3

Conflicts:
	external
Merge branch 'v3' of https://github.com/cocos2d/cocos2d-x into v3
Merge branch 'v3' of https://github.com/cocos2d/cocos2d-x into v3
Merge branch 'v3' of https://github.com/cocos2d/cocos2d-x into v3
Fixed bug with cascade opacity for control button.
Merge branch 'v3' of https://github.com/cocos2d/cocos2d-x into v3
Merge branch 'v3' of https://github.com/cocos2d/cocos2d-x into v3
[NEW]: added pure reference synthesizer
Merge branch 'maz-changes' into v3

* maz-changes:
  [NEW]: added pure reference synthesizer
Added Secure input for CCEditBox on Mac
[NEW]: Implemented NSSecureTextField when CCEditBox inputFlag is set to Password
[FIX]: Cleanup CCEditBoxMac. CCCustomNSTextField class is not needed.
Oops, removed CC_SYNTHESIZE_READONLY_PURE_REF, which is something I added for myself.
Roll back lua PhysicsTest.
Merge pull request #6777 from boyu0/physics_rollback_for_lua

Roll back lua PhysicsTest.
Merge pull request #6774 from Mazyod/v3-mac-secure-input

V3 mac secure input
[ci skip]