def set_metadata(headers)
      log "setting headers for container #{container_path}"
      response = storage_client.post(container_path, '', headers)
      (200..299).cover?(response.code.to_i)
    end
def set_metadata(headers)
      log "setting headers for container #{container_path}"
      response = storage_client.post(container_path, '', headers)
      (200..299).cover?(response.code.to_i)
    end
Set metadata headers on the container

     headers = { "X-Container-Meta-Access-Control-Allow-Origin" => "*" }
     container.set_metadata(headers)

 Note: Rackspace requires some headers to begin with 'X-Container-Meta-' or other prefixes, e.g. when setting
       'Access-Control-Allow-Origin', it needs to be set as 'X-Container-Meta-Access-Control-Allow-Origin'.
 See:  http://docs.rackspace.com/files/api/v1/cf-devguide/content/CORS_Container_Header-d1e1300.html
       http://docs.rackspace.com/files/api/v1/cf-devguide/content/
         POST_updateacontainermeta_v1__account___container__containerServicesOperations_d1e000.html