link to "Schema migration" Wikipedia page. Closes #14479. [ci skip]
[ci skip] Fix Pull Request URL in 4.1 release note.
Merge pull request #14487 from JuanitoFatas/patch/fix-release-note-url

[ci skip] Fix Pull Request URL in 4.1 release note.
Remove Journey from ActionDispatch::Routing::Mapping
cache segment_keys method result
use positive lookbehind to avoid using captures and therefore flattening the match results
Remove some Journey stuff related to parsing paths
almost finished fixing broken tests
scanner no longer needs undo
mounted routes
shit kind of works cept for globs
remove regexp visitor
journey routing test uses new router. path no longer uses ast to construct regexp offests