Update analysis job objects

This adds some functionality to job objects that is needed for the commands selection page. Exists now properly checks the data used for the job, and delete now works for jobs.
Yeah, so I guess you'd have to add another ```if``` statement to avoid firing off that SQL, which makes me think it's not so important to remove this one (that is, the one on this line, 118).  I recommend we just leave this as-is