Registers this plugin as the default instance of VideoPlayerPlatform. Then your VideoPlayer will support all platforms.
If registerWith is not called, the official implementation will be used when available.
options can be
'platforms': a list of Platform.operatingSystem, only these platforms will use this plugin implementation. You can still use official implementation for android and ios if they are not in the list.
If 'platforms' not set, this implementation will be used for all platforms.
