Tweaks to improve these extensions

[bjones1]

Thanks for this. It fixed a frustration that's been unaddressed for years in Sphinx. Great work!

One minor improvement: to avoid Sphinx errors about files not being included a toctree, you can add code in conf.py like:

if not tags.has("tag_used_in_only_directive"):
    exclude_patterns += [ "file_that_is_omitted_by_the_only_directive" ]

I saw this on SO, but can't remember exactly where. This seems like a nice docs improvement for this extension.

Also, an idea: I wonder if there's a way to to set env_version (see extension metadata) returned from setup based on the builder type, which (I think) would force a cache flush / rebuild if the builder changed? That is, set env_version to 0 for HTML, 1 for LaTeX, etc.

[pfalcon]

Thanks for the feedback and suggestions. I for a while no longer use sphinx_selective_exclude, so the project is effectively unmaintained. Feel free to fork and implement these ideas. Otherwise, keeping this open for other folks to be able to find it.