title: Merging Config library
body: <p>Is there anyway to merge two config files the following way:</p>
  
  <pre><code>val conf1= ....
  val conf2= ....
  conf1.withFallbackToPath(conf2,"root.branch2")
  
  **conf1.conf**
  root {
     branch1 {
        value="Hello i am source"
     }
  }
  
  **conf2.conf**
  value = "I am merged"
  </code></pre>
  
  <p>The result of this merge should be :</p>
  
  <pre><code>root {
     branch1 {
        value="Hello i am source"
     }
     branch2 {
        value = "I am merged"
     }
  }
  </code></pre>