V1.51.5

- Fix to be compliant with mapnik 3 grid renderer

- Fix of preview protocol
- Moving towards python 3 compliance

v1.51.4

• Support for GDAL 2.x types OFTInteger64 and OFTInteger64 on Vector Tiles

v1.51.3

version 1.51.3

Fix on the package uploaded to pypi

v1.51.2

• Adding support for .pbf format for Mapbox Vector Tiles
• Configuration can be passed as a dictionary in addition to path to JSON file.