Metadata-edit requests

[drMerry]

I would like 2 extra options for metadata-edit.

In Bulk:
Crop cover - to crop covers for all selected files

In Edit Single:
Apply - To apply new metadata without having to leave the current screen

Spoiler:

This last option is useful in this case:
I often have a book with some info I want to download
But often there is info for several ISBN-numbers. In that case, I want to add the info from several books and save the info between the download tasks.

This is also useful if I download the metadata and afterwards download a cover. If I make an error while downloading the cover, I have to use cancel, this will remove my (first run downloaded) metadata and my cover.