Openamundsen

- Add meteo input format "memory" (68)
- Several small fixes

Enhancements/fixes:

- Several bugfixes/improvements in the evapotranspiration module
- Fix calculation of write dates for gridded outputs (1f00067fadc461f962294c903ec9157c2bcdd067)
- Fix calculation of clear-sky radiation when mean surface albedo is nan (51e206725fc8316b26d7ad2362e9505deaaccff5)
- Fix calculation of (enhanced) temperature index melt (64)
- Allow to resample sub-daily meteo data to daily timesteps (62)
- Add option for resetting state variables in every timestep (66)
- Several additional small fixes/improvements

* Add evapotranspiration module
* Add canopy module

Enhancements/fixes:
* Add grid output formats `geotiff` and `memory`
* Allow station selection by region or ID
* Allow enabling/disabling extrapolation for temperature, precipitation, relative humidity and wind speed
* Improve meteo data reading performance
* Set meteo CRS to main CRS by default when using CSV input
* Calculate clear-sky shortwave irradiance also for outside-ROI stations
* Add method `OpenAmundsen.run_single()` for iterating over time steps
* Use setuptools_scm for handling the package version
* Add tests
* Several bugfixes

Breaking changes:
* Require Python >= 3.7
* Rename `OpenAmundsen.point_outputs` to `point_output`
* Use only within-grid stations by default