Add gpkg generator

[RoelvandenBerg]

Description

Add a command to generate a valid geopackage from a table definition configuration. This helps to create (a template gpkg for) valid geopackages.

We should fix or deal with #102 and #107 (and make the legacy schemas possible) before we merge this.

https://gdal.org/en/latest/development/rfc/rfc31_ogr_64.html

Type of change

• New feature

Checklist:

• I've double-checked the code in this PR myself
• I've left the code better than before (boy scout rule)
• The code is readable, comments are added that explain hard or non-obvious parts.
• I've expanded/improved the (unit) tests, when applicable
• I've run (unit) tests that prove my solution works
• There's no sensitive information like credentials in my PR