Player API for mute/fullscreen incorrect

[pablo]

In the API documentation, we list player.mute() and player.fullscreen() as method calls. However, in the player, they are set up as getter/setters. We should remain consistent with using method calls in the API.

However, this will mean that any plugin using the getters will need an update changing player.fullscreen to player.config.fullscreen, and player.mute to player.config.mute. This update would remain backwards-compatible with 5.0 and 5.1.

If any plugins directly call the setters (e.g. player.mute = false or player.fullscreen = true), they would need to do a player version check. However, I believe the number of plugins actually doing this right now is minimal.

[pablo]

Fixed in 961