physics engine support out of the box ?

[wontheone1]

HI, thanks for writing and maintaining this

I saw how physics can be done with the example of super koalio

but it will be great if library user didn't have to write physics code themselves.

Assigning physics property when specifying :image would be easy to use I think :)

(Also there could be a function that set's the physical properties of the world, gravity for example)