title: Ember-cli implementing custom serializer
body: <p>In an Ember-cli based project with a Rails 4 backend - I need to be able to save (and eventually also read) nested data.  The data model is straight forward ...</p>
  
  <pre><code>Survey
    name: string
  
  Question:
    survey_id: integer
    question_type_id: integer
    text: string
  
  Answer: 
    question_id: integer
    text: string
  
  A Survey hasMany Questions.  Each Question hasMany Answers
  </code></pre>
  
  <p>I'm trying to figure out how write a custom Survey serializer.  Based on my research I know that I need to extend DS.JSONSerializer - but I'm not sure what to do from there.  Any help would be greatly appreciated.</p>
  
  <p>Thanks</p>