M4A improvements

It would be great if all Rekordbox fields can be set with atoms from an M4A file.

Currently the following fields can't be set (suggestion for atom from the file):

• Release Date ("©day" contains: 2020-11-30T00:00:00Z)
• Original Artist ("aART" contains: Tom)
• Composer ("©wrt" contains: Niek)
• Message (N/A)
• Remixer (N/A)
• Mix Name (N/A)
• Label (
      "xid " contains: Label Name:isrc:NLZ54200..
      or
      Atom "----" [com.apple.iTunes;LABEL] contains: Label Name
  )
• Color (N/A)