refactor getScale9Enabled to isScale9Enabled
refactor UIButton
refactor ImageView
refactor Slider control
refactor loadingBar
refactor Layout
fix minor bugs of UISlider and remove unused header include in ListView
refactor, improve imageView stability
refactor, optimize Scale9Sprite
1. remove mac 32bit
2. remove copy files for mac(because of mac use .a instead of dylib)
Merge pull request #7634 from dabingnn/v3_mac_fix

fix some misc issues for mac
Remove CCProtectedNode.h/.cpp from ui/base to 2d and modify the related project setting
Merge branch 'v3' of https://github.com/cocos2d/cocos2d-x into v3_new_module
Merge pull request #7627 from andyque/fixScale9Sprite

refactor ui::widgets to use ui::Scale9Sprite instead of extension::Scale9Sprite
Merge pull request #7635 from samuele3hu/v3_new_module

Remove CCProtectedNode.h/.cpp from ui/base to 2d and modify the related project setting