Describe and recommend the use of the LATEST_LINK variable in
the Committer's Guide ports repo-copy section and in the package naming
section of the Porter's Handbook. In the end, I wrote something that
turned out quite a bit different and somewhat more long-winded than
the suggestions in the PR, but LATEST_LINK was not documented anywhere
until now, so there :)

PR: 66775
Submitted by: eik