show an overview of the import errors/warnings at top of page during catalog import

[MyPyDavid]

Rationale / Begründung

An editor needs a short overview of errors occurring during the catalog import.

At the start of a catalog import all errors/warnings occurring are mentioned next to each imported question. It would be easier if a list of all errors is presented at the top of the import table as well.

Affected

Managers

Minimal functionality

• add an additional paragraph at the top of the management/upload/ section "Warnings"/"Meldungen" and collect there a list or table with all the error messages

Nice-to-have functionality

What sort of related functionality would you like to see in addition?

References / Verweise

• https://github.com/rdmorganiser/rdmo/issues/272
• https://github.com/rdmorganiser/rdmo/issues/465