python3 -m scrapy crawl zapping -o "emptyfile:///tmp/feed.rss" -t zapping
spiders are show-specific as start_url is defined in the file as well as exporters
as show-specific details are hardcoded
basic settings add an rss and <show> exporter, force FEED_STORE_EMPTY = True
and replace the FeedExporter extension class with another class which accumulates
in a PriorityQueue ordered by <now> - <date of episode> and exports them in
reverse chronological order