Add openstack tag to python-redis package

python-redis is now installed by puppet-aodh after
https://review.openstack.org/#/c/433951/ .

We need to use the same tags as used there to avoid
duplicate declaration error.

I think we can't totally remove it and leave it to puppet-aodh
because other services as ceilometer requires it.

Change-Id: I06fb2d51ce42377e8d5a1a2df50119b576a21cea

packstack/puppet/modules/packstack/manifests/ceilometer.pp

@@ -17,7 +17,10 @@ class packstack::ceilometer ()
       $redis_port = hiera('CONFIG_REDIS_PORT')
       $coordination_url = "redis://${redis_host}:${redis_port}"
 
-      ensure_packages(['python-redis'], {'ensure' => 'present'})
+      ensure_resource('package', 'python-redis', {
+        name   => 'python-redis',
+        tag    => 'openstack',
+      })
     } else {
       $coordination_url = ''
     }