kolla-ansible: add prechecks subcommand
kolla-ansible: add prechecks subcommand

TrivialFix

Change-Id: Ifb0ca3383cd04f5ff6baeb30ae6996d450d5c579

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