Double check the Versioneer docs

[Lnaden]

We should consider if we should make a note about the versioneer description to note that it is not really updated, but does still just work. Also double check the LGTM issue (#52) and Flake to ensure the Versioneer files are correctly ignored.

Possible alternate in the future: https://github.com/pypa/setuptools_scm/ (a la @dgasmith)

Notes of when Versioneer might fail in the future:

• Python drops the C-style string formatting (e.g. "%d" % 10). No noted plans to do so at the moment.
• git changes the syntax which Versioneer reads. Very unlikely for the foreseeable future
• setuptools changes the way it accepts additional modules. No sense of the likelihood of this.

[loriab]

I like the look-ahead scheme of setuptools_scm, but switching out seems very low priority. Keeping this open probably provides all the warning a user needs. Though they could be encouraged to always explicitly do zero-patch (e.g., v1.2.0) to be ready for the new tool.

[mattwthompson]

Another option for a possible post-versioneer future: https://github.com/c4urself/bump2version

[Lnaden]

This is superseded by #151.