title: Magento EcomDev PHPUnit Customer fixtures are not being loaded
body: <p>I have a case where i want to check if a customer already exists in the database. I have created a fixture file for this:</p>
  
  <pre><code>scope:
    website:
      - website_id: 1
        code: main
        name: Main Website
        default_group_id: 1
    group:
      - group_id: 1
        website_id: 1
        name: Main Website Store
        root_category_id: 8
        default_store_id: 1
    store:
      - store_id: 1
        code: default
        website_id: 1
        group_id: 1
        name: Default Store View
        is_active: 1
  eav:
    customer:
      - entity_id: 13
        entity_type_id: 1
        website_id: 1
        email: example@example.com
        group_id: 1
        store_id: 1
        is_active: 1
        firstname: john
        lastname: smith
  </code></pre>
  
  <p>When i run the test, i get the error:</p>
  
  <pre><code>Zend_Db_Statement_Exception: SQLSTATE[23000]: Integrity constraint violation: 1052 Column 'sort_order' in order clause is ambiguous
  </code></pre>
  
  <p>This error only occurs when i load the fixture, so i think it has something to do with the Model_Fixture_Eav class. I am not sure which methods i should implement to create an EAV Model for customers. Has anyone managed to successfully import customer fixtures before?</p>