Solution: Make billing configurable through LIBRETIME_ENABLE_BILLING and deactivate it
This should catch all the changes needed to deactive billing in LibreTime.
* [x] only call billing when it is enabled
* [x] let super admins edit their info
* [x] dont link to billing if it is disabled
* CC-6088: Smart Block form needs to have a form layout
* CC-6089: Editor view name fields must be made <input> fields
* CC-6103: Cannot create webstreams
* Reworked a big chunk of the smart block editor flow to send only the
playlist contents back rather than the entire HTML fragment for the
editor.
* Keep more of the playlist/smartblock editor view persistent across
saves, generates, and shuffles.
Lucas Bickel
Albert Santoni
Duncan Sommerville
Robert Elder
Martin Konecny
denise