Dynamic Aspect ratio & app dimensions

[wouterlucas]

We currently support a preconfigured width - height of an application, this works well with TVs as you kind of know what they will be and having a fixed dimension helps with stuff like over scan. On top of that for a long time Browsers in TV devices have been notoriously bad at reporting their window height/width.

However in other devices, or for devices that do report the window width x height properly, we could dynamically setup our dimensions and aspect ratio.