fixes bug 1065145 - Refactor ftpscraper.py crontabber app so it can use config.logger

@rhelmer r?

Sorry, this patch looks much bigger than it is. That's because of a lot of moving things around and indenting them.

I basically took all the `getSomethingxxx()` function and put them into a class called `ScrapersMixin` and then I added a bunch of `self` signatures where appropriate.