Add NAGL Models as a project

[mattwthompson]

Resolves #95 when it works

I mostly looked at where projects are listed and copied stuff over

I think somebody (probably only @lilyminium can) needs to shuffle some perms so this shows up on our docs. subdomain. I haven't done this but maybe @Yoshanuikabundi has written up the process somewhere

[github-actions]

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[mattwthompson]

The lint action is failing because it can't find a URL that doesn't exist

(           index: line   45) broken    https://docs.openforcefield.org/projects/nagl-models - 404 Client Error: Not Found for url: https://docs.openforcefield.org/projects/nagl-models