Improve the copy function of elements (in particular catalogs)

[jochenklar]

Rationale / Begründung

Right now, the copy function for elements is misleading. In RDMO <2.0 the whole catalog was copied, now only the catalog instance is copied. Afterwards managers start to edit questions which are still used in the original catalog. Also, the replacement of a few questions is cumbersome since the corresponding pages and sections need to be replaced manually.

Affected

Managers

Minimal functionality

A solution would be a dedicated copy interface, which lets the user choose which sub element to be (a) kept (b) copied (c) omitted in the new catalog. This would be independent of the data model.

[jwindeck]

great feature!

This should also be possible for option sets