SVN or Git?
This page writes about Mediawiki with SVN in mind. As far as I know, Mediawiki just shifted to Git. And this page should reflect that.
A lot of links are going to SVN from the plural page and from plural/Mediawiki plural rules. When the migration is done, if the links need to be redone, can someone provide the new address of this to set me on the right path?
I have searched the 'trees' at both the addresses you gave and cannot find the files for plural, either in code or in plain language. This doesn't matter as long as the projects which use CLDR or gettext plurals use their own downloads of the CLDR and gettext rules. If so it would perhaps be less confusing to remove the links to these files from the "plural" page anyway?
Perhaps these then: https://gerrit.wikimedia.org/r/gitweb?p=mediawiki/extensions/Translate.git;a=tree;f=data
It's true that CLDR rules are not in our control (projects extract those themselves, usually via i18n framework), but the Gettext rules are authoritative and used like in that file.