Improvements
- Add the image converter to the extra requires ([677](../../pull/677))
- All file tile sources can take either strings or pathlib.Path values ([683](../../pull/683))
- On Girder with read-only assetstores, return results even if caching fails ([684](../../pull/684))
- Handle geospatial files with no explicit projection ([686](../../pull/686))
Bug Fixes
- Fix default properties on annotations when emitted as centroids ([687](../../pull/687))