Tiled maps: examples updated (see the new “strategy game demo”), API and docs improve

[DP News-Robot]

Example examples/tiled/strategy_game_demo was upgraded to use our new TCastleTiledMap component. This is a complete turn-based strategy game using our Tiled integration! As part of this, the game now features map panning and zooming “for free” thanks to the usage of in the viewport. It’s nice to see our approach (“map in viewport is more flexible”) …