BREAKING CHANGE: we've updated the aliases that run `rake` to use
`rails` instead because that's how they are run since Rails v5.
The old `rake` aliases can still be run by using the `rk` prefix
(e.g. the `rake test` alias has been changed from `rt` to `rkt`).

Closes #9601
Closes #9813
Fixes #10696
Co-authored-by: Vsevolod Voloshyn <seva.voloshin@gmail.com>