Zeitwerk simplifies working with dependencies in dev and makes it easier reloading class chains.
We no longer need to use Rails "require_dependency" anywhere and instead can just use standard
Ruby patterns to require files.
This is a far reaching change and we expect some followups here.
Fixes bugs, simplifies code, more default files. General idea, more is more here as it's easier to just delete things than reading and passing all the options.
It is not a setting, and only relevant in specs. The new API is:
```
Jobs.run_later! # jobs will be thrown on the queue
Jobs.run_immediately! # jobs will run right away, avoid the queue
```
Previously if you wanted to have jobs execute in test mode, you'd have
to do `SiteSetting.queue_jobs = false`, because the opposite of queue
is to execute.
I found this very confusing, so I created a test helper called
`run_jobs_synchronously!` which is much more clear about what it does.
