Setuptools-scm

- fix regression in git support - use a function to ensure it works in
egg installed mode

- actually fail if file finding fails in order to see broken setups
instead of generating broken dists

(thanks Mehdi ABAAKOUK for both)

- fix regression in handling git export ignores (thanks Mehdi
ABAAKOUK)

- fix regression in support for old setuptools versions (thanks Marco
Clemencic)

- drop support for eol python versions
- 214 - fix misuse in surrogate-escape api
- add the node-and-timestamp local version scheme
- respect git export ignores
- avoid shlex.split on windows
- fix 218 - better handling of mercurial edge-cases with tag commits
being considered as the tagged commit
- fix 223 - remove the dependency on the internal `SetuptoolsVersion`
as it was removed after long-standing deprecation

- Fix 174 with 207: Reuse samefile backport as developed in
jaraco.windows, and only use the backport where samefile is not
available.

- fix 171 by unpinning the py version to allow a fixed one to get
installed