* Add closed msg field
i18n
fix
* Display based on registration type
* Save as FreshRSS_Context::systemConf()->closed_registration_message instead
* Improve messages
* Revert unrelated changes
* make fix-all
* Minor whitespace
* Simplify logic
* Fix invalid use of empty() and sympler syntax
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Co-authored-by: Alexandre Alapetite <alexandre@alapetite.fr>