Static method called directly by the Core internal Plugins. Key is a reference used to get the plugin from the plugins object (i.e. InputPlugin) Plugin is the object to instantiate to create the plugin Mapping is what the plugin is injected into the Scene.Systems as (i.e. input)
A reference used to get this plugin from the plugin cache.
The plugin to be stored. Should be the core object, not instantiated.
If this plugin is to be injected into the Scene Systems, this is the property key map used.
Core Scene plugin or a Custom Scene plugin?