Create a function that adds margin annotations
Consider this image.
Specific nodes in the SVG are annotated. Can we define:
- a bounding box
- that contains an SVG
- from which specific DOM elements are highlighted
- by a line (straight, bent, curved, clustered, etc)
- connecting to an annotation (arbitrary HTML/SVG)
- whose placement is automatically determined so as to avoid overlap and maximise proximity
- subject to constraints (e.g. place it only on the top, top + right, etc)
This issue needs to be defined better.