Transitions-gui

Release 0.9.0 has been developed to be compatible with `transitions` 0.9.1.

* Updated all npm packages to their recent version
* Aligned minor version to transitions
* Added stub files and `py.typed`
* Extended documentation with styling example
* Added a legend and model names to graphs with multiple models
* Bugfix: Add default machine name to graph when none was passed by markup
* Bugfix 24: Edges with same source not correctly disambiguated for highlighting (thanks Bilby42)

Release 0.1.0 has been developed to be compatible with `transitions` 0.8.2.
Features include:
* move nodes (edit mode)
* trigger events (event mode)
* show conditions, tags, enter/exit callbacks (Url parameter `details=true`)
* auto layout with dagre, cose, bilkent, concentric, etc. (Url paramter `layout=<layout_name>`)
* save current layout by name