Merge config.close into the maptest basic supporting commit 1e33fa0b64c4c79663085999b69fc28216d23d32
TMSLayer test now uses hte new MapTestBasic as well.  same as the xyzlayer test
Make Maptest basic abstract (it should be...), and continue to update tms to use it correctly.
Maybe I don't need to close the outfile specifically? Also, just store the rendering context and use it to access the other pieces of data.

continued cleanup