OpenAtlas

This Easter release was mostly about IIIF and imports.

• IIIF
  • Polygons for annotation selection (#2126)
  • Delete IIIF images (#2106)
  • Display hints for problems (#2146)
• Import: added import for artifacts (#2193), WKT geometries, value types and a lot more (#1567)
• Manual: documentation for sub artifacts (#2241)

A complete list of changes is available here: 8.3.0

• Additional Python packages are required, see upgrade.md