Add geoscript.tile module with mbtiles and geopackage support
Add TileLayer support to the Map Rendering module
Add TileLayer.close() method and use it in the unit tests
Remove fully qualified assert statements
Handle extracting Rasters from TileLayers with Pyramids that have different origins.
Add a getLayer() method to TileLayer to extract the Grid structure as a vector Layer.
Add getSize() method to Grid to return the number of tiles.
Add how long it took to generate the tiles of a zoom level to the verbose output of the TileGenerator.
The TileCursor should reset itself after iterating through all of its tiles.
Add OSM and TMS TileLayers.
Add examples for tile module
Move tile classes to geoscript.layer
Add a UTFGrid TileLayer.  Move Tile rendering from TileGenerator to a TileRenderer.
Clean up used imports and formatting
Introduce ImageTile and ImageTileLayer
Add tile support