Add Manila to the list of images provided by Kolla
Add Manila to the list of images provided by Kolla

Add Manila and its developer website to the list of images
provided by Kolla in README.

DocImpact

Change-Id: Ibaa47c8825464566698d1ae068f5053834ed211a

nihilifer/kolla,dardelean/kolla-ansible,intel-onp/kolla,openstack/kolla,mrangana/kolla,rahulunair/kolla,stackforge/kolla,tonyli71/kolla,negronjl/kolla,dardelean/kolla-ansible,mrangana/kolla,negronjl/kolla,toby82/kolla,nihilifer/kolla,coolsvap/kolla,GalenMa/kolla,toby82/kolla,intel-onp/kolla,dardelean/kolla-ansible,coolsvap/kolla,stackforge/kolla,tonyli71/kolla,mandre/kolla,mandre/kolla,coolsvap/kolla,toby82/kolla,openstack/kolla,rahulunair/kolla,mandre/kolla,stackforge/kolla,GalenMa/kolla,negronjl/kolla