The administration UI should show all the currently used libraries in the book, without any way to change it. A text is explaining that the user should go to each version page to set the configuration.
Each Version page sheet should display the configuration of a library, with a way to add and remove a library configuration. For adding, the library selector should be done thanks to a DBList type in the class. During this time, the library version selector should be greyed out, and then un-greyed.
A page should display in which pages the library (version?) is used.
Libraries won't be added/removed for the whole book at the same time but version by version.
When a new version is created, it should copy the library configuration from the preceding one
Bug
Major
