The changes in this commit were auto-generated by running
tool/migrate.sh
Following this commit, the Dactyl build no longer works but the Redocly
build (mostly) should.
Part of IA and Redocly migration work. Create simple .md files to
represent the automatic index pages that previously only existed in
the dactyl-config.yml file. (The code used to do this is also part
of the commit but is, hopefully, no longer needed.)
Relating to IAv3 and Redocly migration work, this moves introduction
files to match their location in the IA, so that their "pretty" URLs
under Redocly will also match.
