title: can Autofac search for string dependencies in AppConfig
body: <p>is it possible to make autofac fetch for string dependencies in <code>AppConfig</code>/<code>WebConfig</code>?
  I've got some configuration stuff like <code>ConnectionString</code> in <code>WebConfig</code> and I'd like to have autofac fetch it from there and resolve dependencies that refer to it.</p>