* Fix `UploadService is not a class` error.
* Update list of available job classes (remove UploadPreprocessorDelayedStartJob,
UploadServiceDelayedStartJob, add ProcessUploadJob).
Fix the /jobs listing to show retried jobs. GoodJob::ActiveJobJob has a
default scope that filters out retried jobs; remove it in the index
controller so we can see retried jobs.
Also fix mail delivery jobs not showing up in the dropdown in the /jobs
search form.
Add ability to search jobs on the /jobs page by job type or by status.
Fixes#2577 (Search filters for delayed jobs). This wasn't possible
before with DelayedJobs because it stored the job data in a YAML string,
which made it difficult to search jobs by type. GoodJobs stores job data
in a JSON object, which is easier to search in Postgres.
Switch the ActiveJob backend from DelayedJob to GoodJob. Differences:
* The job worker is run with `bin/good_job start` instead of `bin/delayed_job`.
* Jobs have an 8 hour timeout instead of a 4 hour timeout.
* Jobs don't automatically retry on failure.
* Finishing jobs are preserved and pruned after 7 days.
