2D, 2.5D and 3D renderers

# 2D, 2.5D and 3D renderers
2D renderer will warn if a object contains more than 4 vertices (is this possible in the IDE itself?). In the sprite class make sure that an object can only be initialized with exactly 4 vertices.

## Future consideration

The `Editor (TBD)` gives an error in the console when a `Mesh` is initialized with 4 or less `vertices`. When exaclty 4 vertices are given, the console should warn about considering using a `Sprite` component?

## Scene Graph tracking
The scene keeps track of all objects in the game. When they are being rendered, we need to figure out which renderer should be used.

By default, this should be determined by the type of `Renderable` i.e. is the object a `Sprite` or a generic `Mesh`. The developer might have a custom renderer build (see: #19 Custom renderers) so this behaviour should be able to be overridden. The GameObject class should have a `Renderer` property set which the renderes can read to look for if they should render a specific object.

## Automatic Scene Addition via Factory or Manager
When game objects are created they need to be added to the scene in order to be rendered.

To make this something the developer doesn't need to worry about, add the object to the scene using some sort of automatic handler TBD.
The developer should still have control over whether an object should be added into the scene or not manually through a Scene.Add method.