Tries sequentially to find common tags containing episode descriptions
for podcasts when using the generic extractor. Silently allows
description to be None if there are not any found.
According to [1] TABs must be used as separators between fields.
Files produces by some tools with spaces as separators are considered
malformed.
1. https://curl.haxx.se/docs/http-cookies.html
This reverts commit cff99c91d1.