[PROJ] downloadable documentation ?

[Greg Troxel]

I know there are docs on the web, but I have a bias that docs should be
downloadable and packaged, so they can be available offline.

There is a pkgsrc package 'proj-docs', which wraps:

  # \todo See if upstream provides pdf docs, and update if so, or delete if not.
  DISTNAME=               proj-gh-pages
  PKGNAME=                proj-doc-9.1.0
  CATEGORIES=             geography
  MASTER_SITES=           ${MASTER_SITE_GITHUB:=OSGeo/}
  GITHUB_PROJECT=         proj
  # Perhaps associated with 9.1.1, really.
  GITHUB_TAG=             c8132e949948c532e9aef6722ae6eb3e74cbc519

and currently has a single pdf.

I see

  https://github.com/OSGeo/PROJ/tree/gh-pages

but it doesn't seem recent.  I can't figure out if this is what is at
proj.org.

Should I be building proj docs from someplace else?