General TiledView abstraction

There are quite a few usecases where we want to tile visual content of some sort, be it maps, big images, canvas 2D content or similar.

QML API

From the QML side, a sensible API could be a TiledView that provides a delegate which renders each tile. A proper implementation should of course also provide a means of swapping out tiles that are not visible on screen.

C++ API

A more powerful API should be accessible from the C++ side, which allows potentially infinite tile sizes and more control over what the programmer can do.