release strategy relative to ArcGIS Pro versions

[gassc]

Currently we're building the release with the latest available ArcGIS Pro-based Python environment, but have no docs or indicators otherwise of which version of Pro it works with.

It's largely the Python/Anaconda version that might change between ArcGIS Pro releases. Geoprocessing tools may change as well but that's less likely with the tools we're relying on.

Once we start formally publishing releases, we can include that metadata.