Context menu listing other releases is using main information from release,
often it is enough, but sometimes two or more items in the list are exactly
the same, user have to select each one to determine which is matching for him.
This patch is improving a bit the situation by adding packaging, barcode, or even
disambiguation comment if needed.
As an example, it often happens when a CD is released in jewel case and digipak,
with same label, date, country, barcode, etc..
Use more explicit '[no barcode]' instead of '[none]'.
A test case was added for this feature.
