Defines tiled raster layout
extent covered by the layout tiles, could be greater than extent of data in the layer
tile layout (tile cols, tile rows, tile pixel size)
A LayoutScheme is something that provides LayoutLevels based on an integer id or an extent and cellsize.
Transforms between geographic map coordinates and spatial keys.
Layout for zoom levels based off of a power-of-2 scheme, used in Leaflet et al.