WIP: Mount matcher app, migrations and github api setup missing

See https://github.com/rubyrogues/ppwm-matcher/issues/1

If I copy over my `config/application.yml` and `db/development.sqlite3` from my ppwm-matcher app, it works.  (I ran it on http://localhost:9393/match/)

Then then only remaining issues are

1) updating the github app to have the correct callback url (e.g. /match/auth/github/callback )
2) changing the asset paths (e.g. /assets/custom.modernizer.js wasn't found)