sfdisk: more update to the man page

Signed-off-by: Karel Zak <kzak@redhat.com>
sfdisk: add --uuid command

Signed-off-by: Karel Zak <kzak@redhat.com>
sfdisk: add --name

Signed-off-by: Karel Zak <kzak@redhat.com>
sfdisk: cleanup option names

Rename options to --part-{label,uuid,type} to be compatible with
another tools (like lsblk, parts, etc).

Signed-off-by: Karel Zak <kzak@redhat.com>