Switch maintainer to schema.org version

[tmorrell]

Switch maintainer from a codemeta term to the pending schema.org term (https://schema.org/maintainer), as discussed by the Force11 working group in #232. I think I found all the instances, but let me know if I missed any.

This should be tagged for the 3.0 release.

[moranegg]

This PR looks good
if no more comments are added we will merge this PR at the end of March 2023 (included into v3.0)

[progval]

👍 but considering this changes the URI (from https://codemeta.github.io/terms/maintainer to http://schema.org/maintainer), Morane and I decided to postpone this to v4.0 as v3.0 won't have breaking changes in the context.

[ChristianTackeGSI]

Do I understand this change correctly in that "maintainer" would allow Organizations after this change would be implemented for 4.0?

Would the 3.0 release at least allow a list of Individuals?

[progval]

yes, this would allow Organization. It already allows an array of Persons, as any property allowing X also allows arrays of X.

[ChristianTackeGSI]

May I ask what is currently blocking this Pull Request from getting merged for the 4.0 release? Is there anything needing help?

[progval]

It's not yet adopted by schema.org. It's not necessarily an issue but we haven't decided if these are acceptable for Codemeta (AFAIK)

Additionally, this PR needs to be updated to change crosswalks/*.csv instead of crosswalk.csv directly

[stain]

maintainer has been in schema.org since 6.0 (2020) and https://schema.org/maintainer now no longer indicate "pending" but have better wording:

This term is in the "new" area - implementation feedback and adoption from applications and websites can help improve our definitions

btw, the same is true for http://schema.org/provider and which is already added to codemeta.