See a (hierarchical) table of contents of a pad

I find it's hard to keep an overview when editing bigger documents in Etherpad. A table of contents, just like Hackpad would go a long way. But I think we can do better. In combination with the ep_headings plugin it could even be made Hierarchical. Maybe in a later version even collapsable.

I think this would be a great addition to Etherpad, making it a better and free (libre) alternative to say google documents or hackpad.

See the following issue for more info:
https://github.com/ether/etherpad-lite/issues/1273#issuecomment-15347467