Postgis AsMVT() support, remove python2 support

• Generate SQL code to create MVT tiles directly by PostGIS using generate-sqltomvt

  • Currently released openmaptiles/postgis v2.9 has outdated ST_AsMVT support. Use sophox/postgis:latest until new version is released.

• Removed Python2 support

v0.9.2

Removed forgotten debug prints.

v0.9.1

Improved generate-metadata - do not overwrite an existing values by default (except id).
Fixed setup.py for pypi deploy.

v0.9

Fixed and improved generate-metadata

• use env BBOX, MIN_ZOOM, MAX_ZOOM
• clean connection from json

Fixed tests

v0.8

Prepare for wikidata

v0.7

• Remove slice_language_tags (see openmaptiles/openmaptiles#266)
• Add generate-diagram-pngs

v0.6

Do not remove loc_name tag, delete empty keys

v0.5

Extends multilinguality with slice_language_tags function

v0.4

Enables multilinguality: #20

Pixel_scale and ZRES handling added

Adding ZRES to either the tolerance or SQL filter fields will have it replaced with the equivalent zoom and screen resolution maximum possible geographical resolution for better filtering. Pixel_scale is the pixel density and is required in the schema.