title: Is there a way to modify the entity mapping configuration for doctrine outside the config file?
body: <p>In my standard Symfony2-app I'm having a bunch of bundles with some entities. Some of these entities are not located in the standard folder the automapping of doctrine finds out (e.g.  <code>/src/Acme/DemoBundle/Entities</code>) but in a different location.</p>
  
  <p>I could easily use <code>config.yml</code> to tell doctrine to use a different location like this:</p>
  
  <pre><code>doctrine:
      orm:
          auto_mapping: false
          mappings:
             AcmeDemoBundle:
                type: annotation
                prefix: Acme\DemoBundle\Entities\
                dir: %kernel.cache_dir%\Acme\DemoBundle\Entities
  </code></pre>
  
  <p>This works. But say I'm having 10 bundles with a different mapping the <code>config.yml</code> gets bloated very fast. Is there another way, e.g. with a CompilerPass or via DependencyInjection, so I don't need to add all entities in my <code>config.yml</code>? I already looked into the <code>DoctrineBundle</code>, but had no luck so far.</p>