DiskInfo generation refactoring

Only create a DiskInformation object once per DADiskRef in the
dispatcher. That allows DiskArbitrationHandler to reuse the information
which improves efficiency.
Minor logging fix

Make the logging much more readable, with just one data element per line.
UUID Linker

Links disks/volumes by media/volume/device ID. I am unclear what
the various IDs imply, but disk images have volume UUIDs, while
normal volumes and core-storage volumes have both media and volume
UUIDs, and some volumes only have media UUIDs.