Enable debug logging for horizon tests

So that we have more information when they fail.

Change-Id: I3b149cf3466584e4592dba716096931ec32a4e90

manifests/horizon.pp

@@ -37,6 +37,7 @@ class openstack_integration::horizon {
     horizon_key      => "/etc/openstack-dashboard/ssl/private/${::fqdn}.pem",
     horizon_ca       => $::openstack_integration::params::ca_bundle_cert_path,
     keystone_url     => $::openstack_integration::config::keystone_auth_uri,
+    log_level        => 'DEBUG',
     # need to disable offline compression due to
     # https://bugs.launchpad.net/ubuntu/+source/horizon/+bug/1424042
     compress_offline => false,