Resolve "buildings_3d seems unnecessary - palm crashes"

Closes #1

See merge request !2

Draft: Resolve "coordinate variables not filled with data"

Closes #2

See merge request !3

- add command line arguments for dx and dy grid spacing
- implement distance calculations for x and y coordinates
- implement distance calculations for utm coordinates
- adjust README.md

It does not seem to be necessary and causes a crash in palm.

Multiple layers

See merge request !1