[#87160] Email Raw Export general reports as delayed jobs

I know this is going to take a hit in Code Climate because it extracts the CSV generation code out of the view, where it will notice it (update: CC does notice it now, and it hates it). I refactored it lightly this round. The view still exists as it was, but I think it may be dead code now. Tests fail if I remove it, but I don't think it needs to be there if the only "Export Raw" reports are general_reports.

This relied on @mlineen's PR #164 so it's included here. I can rebase it out if that gets merged first.

I'd like to discuss how to handle running the delayed job queue.

There will be a separate PR for the NU fork.
Is this just what delayed jobs generates by default?

I think this could be within `change` method, and then you don't need the drop table as well. Also, this is using 1.8 syntax.