Title underlines should match the length of the title. Unfortunately
docutils only catches underlines that are too short.
Add some missing empty lines after titles.
Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
Currently all shell command docs are put in the doc/usage root.
Let's group them into cmd/ sub-directory.
Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>