Kwcoco

Added
* Add CLI for `find_unregistered_images`

Added
* Add `video_id` argument to `CocoDataset.annots`
* Can now specify render dictionary with `main_ext` and `main_channels` to `random_video_dset` to control demo data file format and the channel codes that are used.

Fixed:

* Prevent resource crash: `find_json_unserializable` now checks for circular references.

* Coco union now handles tracks.

Changed

* The `disjoint_tracks` in `CocoDataset.union` now works on a "track-name"
level. Old behavior where track-ids did not need a corresponding "track"
entry is still preserved but may be removed in the future.

Changed
* Added `imgs_with_annots` to extended stats.
* Background param now works as an argument to `demo` for vidshapes

Fixed
* Added missing `name_to_video` index in sql dataset

Added

* Added `take` and `subgraph` to `kwcoco.CategoryTree`.

Changed

* `kwcoco.CategoryTree` no longer modifies node order to be sorted by id. If
this causes something to break, old behavior can be temporarily restored by
setting `RESPECT_INPUT_ORDER = 0`, but this option will be removed in the
future.

* `kwcoco.CategoryTree.from_coco` and other `CategoryTree` constructors now
respects the order in which the categories were given if id is not present.

Added
* Add `datetime` attribute to `CocoImage`.
* Add `ensure_video` method to `CocoDataset`.
* Add `ensure_track` method to `CocoDataset`.
* Add `sort_values` method to `ObjectList1D` (and hence vectorized `Images` and `Annots` objects).
* Add `--inplace` to `kwcoco conform`.

Fixed
* kwcoco.Coerce with sqlview now works for .kwcoco.zip files.