Annotation list toolbox item

[TrevorBurgoyne]

Borrowing from what I've seen in other annotation tools:

• A list of each annotation (id? or just the idx of the annotation in the ordering?)
  • Option to show/hide deprecated (default hide)
  • Option to group by class
  • Clicking on an annotation should "flyTo" the annotation
• Option to show labels for each annotation with the annotation id or idx
  • Could be shown on hover of an annotation, or drawn next to it on the canvas
• When flying to annotations, show "current idx / total" as a popup or smth

Similar functionality suggested by @joshua-dean in #230 (comment)

[joshua-dean]

Hovering in the annotation list should highlight the annotation in the same way hovering the actual annotation does