title: unable to display foreign key relationship in Django rest framework
body: <p>I have a model Project, Tasks, and Project has many Tasks, I'm trying to list all tasks under each project. </p>
  
  <pre><code>GET /api/project/ 
  
  HTTP 200 OK
  Allow: GET, POST, HEAD, OPTIONS
  Content-Type: application/json
  Vary: Accept
  
  [
      {
          "id": 2,
          "name": "Project 2",
          "task": [
              3
          ]
      },
      {
          "id": 1,
          "name": "Project 1",
          "task": [
              4,
              2,
              1
          ]
      }
  ]
  </code></pre>
  
  <p>I'm unable to display details of each Task, Task name, description, status ..etc </p>
  
  <p>Here is my Serializer</p>
  
  <pre><code>from rest_framework.serializers import ModelSerializer
  from api.models import Project, Task
  
  
  class ProjectSerializer(ModelSerializer):
      class Meta:
          model = Project
          fields = (
              'id',
              'name',
              'task'
              )
  
  
  class TaskSerializer(ModelSerializer):
  
      class Meta:
          model = Task
  </code></pre>
  
  <p>Here is my Model</p>
  
  <pre><code>class Project(models.Model):
  
      # Fields
      user = models.ForeignKey(User)
      name = models.CharField(max_length=255)
  
      # Relationship Fields
      #user = models.ForeignKey(settings.AUTH_USER_MODEL, )
      user = models.ForeignKey(User)
  
      class Meta:
          ordering = ('-created',)
  
      def __unicode__(self):
          return u'%s' % self.name
  
  
  class Task(models.Model):
  
      # Fields
      name = models.CharField(max_length=255)
  
      # Relationship Fields
      project = models.ForeignKey('Project', related_name='task' )
  
      class Meta:
          ordering = ('-created',)
  
      def __unicode__(self):
          return u'%s' % self.name
  </code></pre>