Updates to the image registry doc
Updates to the image registry doc

Signed-off-by: Martin Hickey <5a111d7c144d6e07073f7da1705506e1d8bdbf43@ie.ibm.com>

vdemeester/containerd,containerd/containerd,dmcgowan/containerd,mikebrow/containerd,vdemeester/containerd,thaJeztah/containerd,thaJeztah/containerd,estesp/containerd,containerd/containerd,mikebrow/containerd,dmcgowan/containerd,estesp/containerd