* Bump the dev part to "dev.2"
* Add stubby setup.py file for compatibility with python 3.6
* Deprecate cli functions imported from root
* Revert to `pysemver` as console script.
* Refactor __main__.py
  * add type hints for correctness
* Rename VersionInfo to Version to close python-semver#305
* Refactor and integrate suggestion from @tomschr
  * Create :file:`src/semver/cli.py` for all CLI methods
  * Create :file:`src/semver/_deprecated.py` for the ``deprecated`` decorator and other deprecated functions
  * Create :file:`src/semver/__main__.py` to allow calling the CLI using :command:`python -m semver`
  * Create :file:`src/semver/_types.py` to hold type aliases
  * Create :file:`src/semver/version.py` to hold the :class:`VersionInfo` class and its utility functions
  * Create :file:`src/semver/__about__.py` for all the metadata variables
* Adapt infrastructure code to the new project layout.
  * Replace :file:`setup.py` with :file:`setup.cfg` because the :file:`setup.cfg` is easier to use
  * Adapt documentation code snippets where needed
  * Adapt tests
  * Changed the ``deprecated`` to hardcode the ``semver`` package name in the warning.
* Change path for docformatter and run it.
* Remove pyi inclusion from black sine we aren't using them
* Split up changelog to make more sense.
* Add documentation for Version rename
* Increase coverage to 100% in non-deprecated parts.
* Update changelog.d/169.feature.rst

Co-authored-by: Thomas Laferriere <t.laferriere@hotmail.ca>
Co-authored-by: Tom Schraitle <tomschr@users.noreply.github.com>

Acoording to the mentioned PEP:

  "Package maintainers who wish to support type checking
   of their code MUST add a marker file named py.typed
   to their package supporting typing."

Add package_data to setup.cfg to include this marker in dist
and whl file.

Split changelog entries into semver 3 (new) and semver 2 (old).

Create a separate file to describe how to migrate to new
semver3.

* Use sphinx-apidoc to build API documentation
* Amend tox.ini and call sphinx-apidoc
* Remove old autosummary; it turned out it was difficult to
  configure and returned warning messages which were hard to fix.
* Add semver version in footer
* Add semver.__about__ to API doc
  * Unorthodox solution with sed
  * Remove obsolete config variables in docs/config.py
  * Add docs/_api/semver.__about__.rst as a placeholder
* Add changelog.d/304.doc.rst

(An old attempt was to use autosummary from https://stackoverflow.com/a/62613202;
however, that didn't work quite well.)

Co-authored-by: Tom Schraitle <tomschr@users.noreply.github.com>