title: Save values global in NodeRED
body: <p>We are working with MQTT messages, process these messages and call a REST service to send the information to another system.</p>
  
  <p>Now we need to save some values from the MQTT message to compare these values with other messages. Is it possible to create an array that is outside the workflow that can be accessed from other workflows? Currently we are saving the values to a file but this is not the way we want to do it.</p>