Prompt the user to supply a Disc name on capture

[gregjan]

When the capture set includes a Disc root, look for a volume label and prompt the user with a dialog allowing them to edit it.

This is especially helpful with Windows removable discs, where each disc has the same path by drive letter. However it will also help on Macs and Linux, where two discs can easily have the same volume label.

How does this sound?

Do the best we can to extract the volume label from the filesystem.
Present this value as the original's default name for edit by the user in the link originals wizard.
Form validation must include that this value be a unique original name.