Edit Metadata revision

[Grizzly127]

When editing the metadata the Stepper is not necessary, it is one dialog that can be edited and confirmed.
Therefore we use the heading "Edit metadata".
The options get one consistent icon.
The optional metadata can be collapsed, but are open by default.
We integrate the new input fields that should be used gradually everywhere.
Maybe some fields will be removed, this will be discussed with @ZetOE

Here is the first impression of the changes and the new design, the rest will follow when the concrete fields that we want to keep are discussed.