Create a primewire scraper

This PR moves all the website related code into a single scraper class. This drastically simplifies default.py and cuts down on LOTS of cut-and-paste reuse that is in the existing code.  I've tested it quite a bit and think I've caught any issues. I also fix a few miscellaneous bugs like some urls returning unplayable, favorites not refreshing on a migration, adding timers to url fetches,