title: Return single property with spring-boot repository
body: <p>Today I use spring-data-jpa to create my queries.<br>
  Is it possible to return only one property from the object?<br>
  For example:</p>
  
  <pre><code>public interface UsuarioRepository extends MongoRepository&lt;Usuario, String&gt; {
  
      String findNameByMailAndPassword(String mail, String pass);
  
  }
  </code></pre>
  
  <p>I want to return only the name, not the whole <code>Usuario</code> object.</p>