Swisslandstats-geopy

- affine_transform as instance property

- fix `to_geodataframe` method
- auto extract crs from geoseries

- added to_geopandas methods

- added merge class method and module function

- geometry clip functions as LandDataFrame class methods
- fix colormap and legend bug

- initial release
\[v0.11.0\]: https://github.com/martibosch/swisslandstats-geopy/compare/v0.10.0...v0.11.0
\[v0.12.0\]: https://github.com/martibosch/swisslandstats-geopy/compare/v0.11.0...v0.12.0