* Produces a data flow in the RSS format
* add documentation and rss reference
* more complete rss component, with support for podcasts
* podcast changes
* documentation
* format dates as rfc2822
* extract template helpers
* extract more helpers
* remove unnecassary error handling
* fmt
* two-param helpers
* rfc2822_date_helper
* test rfc date formatter
* accept dates with or without time
* remove unneeded line breaks
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Co-authored-by: Olivier Auverlot <oauv@duck.com>
Co-authored-by: lovasoa <pere.jobs@gmail.com>