add some more text to the cli docs
add some more text to the cli docs

Docker-DCO-1.1-Signed-off-by: Sven Dowideit <SvenDowideit@fosiki.com> (github: SvenDowideit)

cpuguy83/cli,e11137/cli,e11137/cli,redpanda/cli,ashfall/cli,docker/cli,Zebrilee/cli,thaJeztah/cli,allencloud/cli,riyazdf/cli,dnephin/cli,docker/cli,ashfall/cli,redpanda/cli,riyazdf/cli,Zebrilee/cli,thaJeztah/cli,cpuguy83/cli,allencloud/cli,dnephin/cli