Metadata fields are not alphabetically sorted

[jduehring]

When changing the Metadata in the Editor, the selectable dropdown lists are not alphabetically sorted.

In my opinion it would make sense to have them sorted.

[mtneug]

Not sure about the default ordering, but listproviders can have a user-defined order (e.g. s. licenses.properties). IMO, the editor should primarily respect that. But falling back to sorting by name makes sense to me.