[plug] logging incomplete downloads in Apache

[Craig Ringer]

Hi folks

I was wondering ... does anyone here know of a way to get Apache to log
downloads that are not completed? The POST is currently serving up some
large PDFs, and while we're getting lots of _hits_, I don't know how
many of those are prematurely terminated. In this case, that's important
information, because it's the difference between a successful download
and a user saying "stuff it, this is taking forever."

Craig Ringer