checksums for audio solution pack

Allow users to enable checksumming the OBJ datastream, and allow users to select checksum type if checksumming is enabled.

Not sure if this is the best approach in so far as enabling checksumming. Should we do this on individual solution pack or at a higher level, like the Islandora configuration page, or a checksum solution pack?

If this is the right approach, I can take care of writing this the for other main solution packs.