title: Use of an external java class as a type in an AVRO schema
body: <p>Is it possible to refer in an avsc file to a Java class already implemented?</p>
  
  <p>My idea is to have something like:</p>
  
  <pre><code>{
      "namespace": "com.myCompany.myProject.schemas",
      "type": "record",
      "name": "SimpleTest",
      "fields": [
        {"name": "text","type": "string"},
        {"name": "myOtherObj","type": "com.myCompany.myProject.MyClass"}
        ]
  }
  </code></pre>
  
  <p>where the field <code>myOtherObj</code> has as type the already defined java class <code>MyClass</code> that is already build.</p>