Tilemapbase

- Stop noisy logging, see https://github.com/MatthewDaws/TileMapBase/issues/13
- Parse the new geoPandas CRS code, see https://github.com/MatthewDaws/TileMapBase/issues/19
- Some error handling around lon/lat, see https://github.com/MatthewDaws/TileMapBase/issues/23

- Stop caching invalid responses from remote server: https://github.com/MatthewDaws/TileMapBase/pull/16
This fixes https://github.com/MatthewDaws/TileMapBase/issues/3

- OSM now needs headers: https://github.com/MatthewDaws/TileMapBase/pull/10
- https://github.com/MatthewDaws/TileMapBase/issues/11

- Add option to `to_expect` method to allow enlarging the rectangle.

- Add Extent static constructors from epsg:3857 coords
- Work to allow uploading to PyPi:
- Download and install `pandoc`
- `pip install pypandoc`
- Delete the `dist` directory
- `python setup.py sdist`
- `pip install twine`
- The following assumes ".pypirc" has been written correctly (see https://packaging.python.org/specifications/pypirc/)
- `twine upload --repository pypitest dist/*`
- If you get an error, maybe I have already uploaded, and then deleted, the same version. Try changing the version by adding letters.
- Test: ``
- More instructions here: https://packaging.python.org/tutorials/packaging-projects/

- Allow SQLite cache to operate across multiple threads.