Clean up old files on old RECAP server

[mlissner]

So, I'd love to decommission the old recap server in #209, but, alas, there's still some good stuff on there:

• The main table in the RECAP DB has 42M rows. That's a lot more than what we have on CourtListener right now. Why?

• There are at least 60k files (PDFs, dockets as XML, etc.) that are sitting around. This usually means they didn't get uploaded. Why?

I'm moving all this content to the CourtListener server right now, but it's worth digging into these a bit to see how much of this content we can add to the new RECAP Archive, since it didn't get added to the old.

[mlissner]

I don't see this ever happening, honestly. I think we got all we can from it. The data is still around somewhere, I think, so if we ever want to revisit it, great, but the data is getting older and less useful by the day, and I don't see it happening.