Correct type in name of archived_jobs_controller.rb
Add engine link to dummy app page.
Adding routes for archived_jobs

Also added links from the Jobs#index to the ArchivedJobs#index and vice
versa.
Added placeholder links for a failed job.
Allow for creation of a job that will fail

To create a failing job you should enter a message of 'ERROR'
Reedefining how the Status of a Delayed::Job is determined.