Patch release for compatibility with Xcode 12, adding new messageCenterStyle
properties to the default message center UI classes to avoid conflicting with
UIKit changes in iOS 14. The original style properties will continue to be
available when compiling with Xcode 11, but are not available in Xcode 12.
Apps that wish to remain on 13.x while developing on iOS 14 are encouraged
to upgrade.
- Added new messageCenterStyle properties to the default message center UI