Adds relative partition sizing and placement options for both start and
end sectors; improves hybrid MBR synchronization (deletes matching MBR
partition when a GPT partition is deleted, warns about inconsistencies
when verifying or writing a partition table).
This version adds support for FreeBSD and big-endian systems. It also
adds support for BSD disklabels and an assortment of other changes,
improvements, and bug fixes.