Hyperspy-gui-ipywidgets

* Fix test suite after `eXSpy` API changes in [hyperspy/exspy59](https://github.com/hyperspy/exspy/pull/59) ([#69](https://github.com/hyperspy/hyperspy_gui_ipywidgets/pull/69))

* Fix incorrect library version ([64](https://github.com/hyperspy/hyperspy_gui_ipywidgets/pull/64))

* Add releasing guide and release script ([59](https://github.com/hyperspy/hyperspy_gui_traitsui/pull/59)).
* Add `ipympl` dependency as convenience ([58])(https://github.com/hyperspy/hyperspy_gui_ipywidgets/pull/58).
* Fix regression with editable installation ([55](https://github.com/hyperspy/hyperspy_gui_ipywidgets/pull/55)).

* Consolidate package metadata in `pyproject.toml` ([49](https://github.com/hyperspy/hyperspy_gui_ipywidgets/pull/49)).
* Support HyperSpy 2.0 and set HyperSpy requirement to >=2.0 ([48](https://github.com/hyperspy/hyperspy_gui_ipywidgets/pull/48)).

* Improve rendering changelog on github and fix hyperlinks in `README.md` ([41](https://github.com/hyperspy/hyperspy_gui_ipywidgets/pull/41)).
* Speed up import time by importing submodules lazily and drop support for python 3.6 ([40](https://github.com/hyperspy/hyperspy_gui_ipywidgets/pull/40)).
* Add python 3.10 to github CI and update github actions versions ([42](https://github.com/hyperspy/hyperspy_gui_ipywidgets/pull/42)).
* Add GUI for the calibration method of signal2D ([2](https://github.com/hyperspy/hyperspy_gui_ipywidgets/pull/2))