feat: add podcast:season and podcast:episode tags to rss feed
requested to merge NeoluxConsulting/castopod:add-season-and-episode-podcast-namespace-tags-to-RSS into develop
The Podcasting 2.0 spec defines the tags <podcast:season> and <podcast:episode> as almost identical to the itunes namespace tags.
It is low-hanging fruit to support these tags as duplicates, and to be able to have increased support for the podcast namespace. As the podcastindex.com app list is based on the number of tags supported, this will push Castopod up the list, which should mean more podcasters consider Castopod as a host.
