Datadigitizer

* Switch to source structure with **src/package**.
* Add configure.sh and Makefile for building the documentation and the sdist and wheel packages.
* Switch to mostly markdownd, through myst-parser, for the sphinx documentation.
* Drop support for Python 3.8 (end of life).
* Increase minimal version of Numpy to >=1.22.
* Add executable scripts for running gui: **datadigitizer**.

Full changelog available at [github](https://github.com/MilanSkocic/pydatadigitizer/releases)

* Switch to pyproject.toml.

Full changelog available at [github](https://github.com/MilanSkocic/pydatadigitizer/releases)

* Refractoring and code cleaning.

Full changelog available at [github](https://github.com/MilanSkocic/pydatadigitizer/releases)

* Change of numpy minimum version from 1.17 to 1.20 for taking advantage of the typing module.
* Change of matplotlib minimum version from 3.0 to 3.4 for taking advantage of new features.
* Simplify the settings in init file.

Full changelog available at [github](https://github.com/MilanSkocic/pydatadigitizer/releases)

* Minor fixes in documentation.

Full changelog available at [github](https://github.com/MilanSkocic/pydatadigitizer/releases)

* Minor fixes in documentation.

Full changelog available at [github](https://github.com/MilanSkocic/pydatadigitizer/releases)