Kwimage

Added

* Basic CLI with the `stack_images` command.
* Workaround for `colorize` when heatmap is an index raster with negative ignore values.

Added:

* Add `drop_non_polygons` argument to `_ShapelyMixin.fix`.

* Changed: argument to `grab_test_image_fpath` can now be an existing path and
it will return that. (allows users to substitute custom images for demodata).

* Added `clip`, `shape`, `endpoint`, and `wrap` argument to `Box.from_slice`


Changed

* Can now call `draw_header_text` without an image argument.

Added

* `kwimage.Affine.fliprot` - a constructor that creates a transform equivalent to a flip and rotation with the positive image quadrant
* `kwimage.Boxes._ensure_nonnegative_extent` - experimental box method to fix negative width/heights


Fixed

* `draw_on` methods for `Boxes`, `Polygon`, and `Points` no longer crashes if you pass it an image with 0 width or height.
* Fixed error in `subpixel_setvalue` where the coordinate extents did not
always match the requested axes (e.g. sometimes the y axis would be clipped by width)

Added
* Added a too-big check in `imwrite` for better error messages.

Changed
* Modified paths of augmented demodata to remove bad path characters.
* `Boxes.from_slice` now allows the left coordinate to be bigger than the right in the case you are clipping.

Fixed
* Fixed issue when giving `Affine.coerce` an empty dictionary
* Issue in box `intersection` / `union_hull` with integer data
* Fixed `Box.to_coco()`

Added
* intersection to Box class.

Changed
* `grab_test_image` now falls back to mirrors if the first URL returns an error
* Allow `format` to be positional in `kwimage.Box.coerce` and `kwimage.Boxes.coerce`

Fixed
* Fixed compatibility with new scikit-image
* Mixin methods are now shown in the docs