Pdok 18835/vervanging trex v2 merge gpkgs

[DvBree]

Description

texel mvt now has support for processing multiple input geopackages. The input files are configured using a toml file, specified via --config or -c. This is set up in such a way that a trex toml file should work (though not all fields are required).
In addition, when texel snap is running with encoding, it records the zoomlevel of the encoded geometries (i.e., multiple zoom levels are now supported). This also means that texel mvt now requires an additional argument, -z to specify the target zoomlevel for tile generation.

Type of change

• New feature
• Configuration change

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