Setuptools-scm

- fix 395: correctly transfer tag regex in the Configuration
constructor
- rollback \--first-parent for git describe as it turns out to be a
regression for some users

- pull in 377 to fix 374: correctly set up the default version
scheme for pyproject usage. this bugfix got missed when rushing the
release.

- fix 181 - add support for projects built under setuptools
declarative config by way of the
setuptools.finalize_distribution_options hook in Setuptools 42.
- fix 305 - ensure the git file finder closes file descriptors even
when errors happen
- fix 381 - clean out env vars from the git hook system to ensure
correct function from within
- modernize docs wrt importlib.metadata

*edited*

- use \--first-parent for git describe

- add eggs for python3.7 and 3.8 to the deploy

- fix 335 - fix python3.8 support and add builds for up to python3.8

- fix 333 (regression from 198) - use a specific fallback root when
calling fallbacks. Remove old hack that resets the root when
fallback entrypoints are present.