Merge pull request #2732 from dougbtv/openstack_shade_fix

[openstack] updates documentation to show that you need to install shade

README_openstack.md

@@ -25,6 +25,7 @@ On Fedora:
 On RHEL / CentOS:
 ```
   yum install -y ansible python-novaclient python-neutronclient python-heatclient
+  sudo pip install shade
 ```
 
 Configuration