We should not use /dev/sda and /dev/sdb in our examples. Users might
inadvertently mess up their workstation. Use /dev/sdX instead.
Remove console output like '# ' and '> ' which makes copying hard.
Set example language to bash for correct syntax-highlighting.
Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
iewed-by: Bin Meng <bmeng.cn@gmail.com>