Documentation: explain non-root capabilities
Documentation: explain non-root capabilities

kinvolk/rkt,coreos/rkt,joshix/rkt,lucasallan/rkt,joshix/rkt,coreos/rkt,lucasallan/rkt,lucasallan/rkt,rkt/rkt,kinvolk/rkt,rkt/rkt,joshix/rkt,kinvolk/rkt,lucasallan/rkt,rkt/rkt,joshix/rkt,coreos/rkt,kinvolk/rkt,rkt/rkt