Added "exclude_files" option for pyproject.toml config usage.

[mattgebert]

Added an option for a exclude_files option in pyproject.toml config that allows re regular expression path exclusions.

Unfortunately, most yaml tags use exclude to refer to files, which perhaps doesn't apply to toml, but we already use the exclude label to notate object exclusion. I have introduced exclude_files instead to achieve the same purpose, which is almost processed identically to exclude except being utilized instead when iterating over the run_hook filepath list.

I'm not familiar with the Sphinx build checking options that exclude currently uses. Do I/we need to implement a mapping for this in that location too?

Solution to Issue #497

[larsoner]

I'm not familiar with the Sphinx build checking options that exclude currently uses. Do I/we need to implement a mapping for this in that location too?

I think ideally yes so that the hook and the Sphinx-based checking both function similarly. In principle they should use 99% of the same mechanics so hopefully it won't be too hard to add at the Sphinx end...

[mattgebert]

@larsoner Thanks mate. I've figure that out now. I think the implementation is succinct. I currently don't have any projects with a sphinx production (in the process of setting up my first) so it would be good if someone else can see if it behaves as intended. The new test cases work.

I've also updated the documentation to mimic exclude (pyproject.toml) / numpydoc_validation_exclude (sphinx) for exclude_files.

I have one concern about using the __file__ attribute of the module for checking the exclude Sphinx extension - do you think I ought to point the regex matching to the path relative to the package root, or the global path (the current implementation)?

[mattgebert]

Possibly problematic to get global path to module file, rather than relative path to a package root? Perhaps this is fine.