title: Can not save a Point into EmbeddedDocument MongoDB Dlask Mongoengine
body: <p>I'm using:
  python: 3.4.2
  MongoDB: 3.2
  Flask: 0.10.1
  MongoEngine: 0.10.6</p>
  
  <p>I'm trying to save a point into a PointField using code below:</p>
  
  <pre><code>from mongoengine import StringField, PointField, \
                          EmbeddedDocument, Document, EmbeddedDocumentField
  
  
  class Location(EmbeddedDocument):
      name = StringField()
      point = PointField()
  
      def __str__(self):
          self.name
  
  
  class Person(Document):
      name = StringField()
      location = EmbeddedDocumentField(Location)
  
      def __str__(self):
          return self.name
  </code></pre>
  
  <p>On console try this:</p>
  
  <pre><code>&gt;&gt;&gt; location = Location()
  &gt;&gt;&gt; location.name = "Arroz"
  &gt;&gt;&gt; location.point = {"type": "Point", "coordinates": [12,22]}
  &gt;&gt;&gt; person = Person()
  &gt;&gt;&gt; person.name = "Juan"
  &gt;&gt;&gt; person.location = location
  &gt;&gt;&gt; person.save()
  </code></pre>
  
  <p>But when I try to save() launch an except:</p>
  
  <pre><code>mongoengine.errors.OperationError: Could not save document (location object expected, location array not in correct format)
  </code></pre>
  
  <p>Any idea what's happening?</p>