Fix gerrit installation
Fix gerrit installation

 * Ensure we have directory, before putting any content there
 * nginx should be installed before putting certs
 * provide correct sequence for installing gerrit

Change-Id: I5b9593b7acc5702cb12365b3b8612aefc828d3c7
fuel-infra/puppet-manifests,fuel-infra/puppet-manifests,fuel-infra/puppet-manifests,fuel-infra/puppet-manifests