Add docker support kafka in README.rst
Add docker support kafka in README.rst

Change-Id: I8dc7f1e8b3dcd7dae26181266580cafbe6cdec33

rahulunair/kolla,GalenMa/kolla,intel-onp/kolla,intel-onp/kolla,openstack/kolla,mrangana/kolla,stackforge/kolla,mrangana/kolla,GalenMa/kolla,stackforge/kolla,coolsvap/kolla,nihilifer/kolla,nihilifer/kolla,openstack/kolla,coolsvap/kolla,stackforge/kolla,rahulunair/kolla,coolsvap/kolla