title: geocoder undefined method `coordinates='
body: <p>On rails 3.2.11, geocoder version 1.1.8</p>
  
  <p>in my model:</p>
  
  <pre><code>  class Venue
      include Mongoid::Document
      include Geocoder::Model::Mongoid
      ....
      field :address, type: String
      field :latitude, type: Float
      field :longitude, type: Float
      ....
  
      geocoded_by :address
      after_validation :geocode, :if =&gt; :address_changed?
      .....
    end
  </code></pre>
  
  <p>and when I try to create a new venue I get an error traced to the controller at Venue.create</p>
  
  <pre><code>undefined method `coordinates=' for #&lt;Venue....
  </code></pre>
  
  <p>To cut to the chase I have run bundle install and restarted the app server since installing the gem. </p>
  
  <p>Thanks in advance.</p>