cheap image dump script that might be ok for wikitech
[WIP] This runs ok on enwiki on beta, on snapshot01 instance, using
the included config file; in the real world it may yet need help. Lots
of error handling probably missing.
It also runs ok on wikitech-static, pulling images from wikitech.
That doesn't mean it's suitable for cron yet.
It is supposed to raise an exception if too many image retrievals
or too any cp of image from past dump fail in a row, but this
needs to be tested in a broken setup.
- relies on direct access to db, want to fix that
- does not retrieve media on commons used on the wiki, only local media
- no scaling, retrieves originals only