Nested block detailed attributes

[streamich]

Inline formatting:

• [ ] Get data view
• [ ] Get data as "obj" node
• [ ] Events
  • [x] Insert
  • [ ] Delete
  • [x] Invert selected
  • [x] Erase selected
  • [ ] Update data
  • [ ] Overwrite data

Block markers:

• [ ] Events
  • [ ] Set whole type in one operation, insert marker
  • [ ] Delete whole marker (block split)
  • [ ] Delete N tags at index
  • [ ] Insert tags (tag, data, discriminant) at index
  • [ ] Change tag at index
  • [ ] Change discriminant at index
  • [ ] Change data at index
• [ ] Retrieval API
  • [ ] Get whole type as view
  • [ ] Get data as "obj" node at index