Files in doc/cli/*.md are used in and displayed as help text in the CLI
admin-exec level. So we cannot use standard admonitions (yet) since the
terminal markdown converter (lowdown) doesn't support the syntax.
Signed-off-by: Joachim Wiberg <troglobit@gmail.com>
Also, add a new `quick.md` that pops up when the user types `help`.
Very quick intro to get started. Useful when we add a factory-default
motd: "Welcome to the CLI, type 'help' for a quick overview."
Signed-off-by: Joachim Wiberg <troglobit@gmail.com>