Support for multiple resolutions

[vreelb]

Now that RPI TV 4K is going to be a thing it might be a good time to look into options for rendering at different sizes and aspect ratios, something I had thought about in the past but was never of great importance.

All this would really entail is having the options set by the user and using them to compute how imagemagick should render, since the majority can be rendered at any size (the only limit on them looking good is the size of embedded images).

[hamilr2]

There would probably need to be some re-working of the drawing methods to make the design work better at 2x -- single pixel strokes and shadow distances would need to be doubled outside of the dimensions of each geo.

Otherwise yeah, double every pixel value in a template XML and voila: 4K.

[vreelb]

Yeah I figured it would just take some scaling logic for 16:9 resolutions, and padding/scaling logic for others (others really meaning 4:3, but while we're at it might as well just make it support cinematic ones as well for the hell of it).

Do we want this set at event level? I could see this being really useful if we end up straddling two resolutions like we did in the past with HD/SD. All you'd need to do is change the event from HD to 4K and re-render all titles.