title: How do I get an instance of a Grails service programmatically?
body: <p>I have an external data source, which will return a string indicating the name of a Grails service to use.</p>
  
  <p>What's the syntax to get an instance of this service programatically given the name of the service as a String?</p>
  
  <p>ie. given 'GoogleWeather', give me an instance of GoogleWeatherService.</p>
  
  <p>Thanks!</p>