title: How to customize MappingMongoConverter (setMapKeyDotReplacement) in Spring-Boot without breaking the auto-configuration?
body: <p>How could I customize the <a href="http://docs.spring.io/spring-data/data-mongo/docs/current/api/org/springframework/data/mongodb/core/convert/MappingMongoConverter.html" rel="noreferrer"><code>MappingMongoConverter</code></a> within my Spring-Boot-Application (1.3.2.RELEASE) without changing any of the mongo-stuff which is autoconfigured by spring-data?</p>
  
  <p>My current solution is:</p>
  
  <pre class="lang-java prettyprint-override"><code>@Configuration
  public class MongoConfig {
  
    @Autowired
    private MongoDbFactory mongoFactory;
  
    @Autowired
    private MongoMappingContext mongoMappingContext;
  
    @Bean
    public MappingMongoConverter mongoConverter() throws Exception {
      DbRefResolver dbRefResolver = new DefaultDbRefResolver(mongoFactory);
      MappingMongoConverter mongoConverter = new MappingMongoConverter(dbRefResolver, mongoMappingContext);
      //this is my customization
      mongoConverter.setMapKeyDotReplacement("_");
      mongoConverter.afterPropertiesSet();
      return mongoConverter;
    }
  }
  </code></pre>
  
  <p>Is this the right way or do I break some stuff with this?<br>
  Or is there even a more simple way to set the mapKeyDotReplacement?</p>