It's mostly spelled BTRFS anyway in our documentation (and also the
official casing AFAICS), so align a few instances where it spelled
lowercase.
Signed-off-by: Christoph Heiss <c.heiss@proxmox.com>
To ensure it's clear for user that they should use UUIDs, and to
provide more clear instructions for those not accustomed to the CLI.
Signed-off-by: Thomas Lamprecht <t.lamprecht@proxmox.com>
