Mkdocs-drawio-exporter

* Test the most crusty Python version we claim to support
* Fix Python 3.8 regressions introduced in 0.9.0:
* Work around f-string substitution parsing limitation
* Fix type annotation breakage by importing `__future__.annotations`

* Migrate to Poetry for dependency management
* Update all of our ailing dependencies
* Use `Logger.warning` over `Logger.warn` to fix deprecation warnings
* Document `--embed-svg-images` for shape libraries
* Support inlining SVG content with `embed_format: '{content}'`; props herberton
* Fix handling of diagram filenames containing spaces

* Allow embedding SVGs inline or with `<object>`
* Update dependencies

* Handle missing executable by exiting
* Honour a passed `drawio_executable`
* Correctly handle Program Files (x86) on 64-bit Windows
* Update dependencies

* Fix handling of cached files

* New `drawio_args` option allows passing additional args to the Draw.io CLI
* Improve handling of cases where Draw.io reports a successful export but doesn't write an output file