Add profile usage to kolla-build guide
Add profile usage to kolla-build guide

It's not uncommon case which user need defined set of images to
use in their scenario.

TrivialFix

Change-Id: I903220def8ce263a51257380a19ae9ea67fb4cd5

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