dependency on unmaintained click-plugins

[stanislavlevin]

click-plugins (https://github.com/click-contrib/click-plugins) is unmaintained for over 6 years and looks incompatible with click 8.2.0 (click-contrib/click-plugins#38).

This is a blocker for using click 8.2.+.

[geowurster]

@sgillies As part of shutting down click-plugins, I have reworked the core module to better support vendoring. I'm happy to open an MR for vendoring the library, or one that implements the same functionality without click-plugins.

click-contrib/click-plugins#40

[geowurster]

I have completed the work on click-plugins, and am available to work on migrating Rasterio in the near future. Just need a decision on the approach.

A similar effort for Rasterio is tracked in rasterio/rasterio#3353.