title: Custom Assetic Filter
body: <p>Is any posibilities to include service file with assetic filter definition as YML file in config.yml? Assetic expects XML structure...</p>
  
  <p>bundle/Resources/config/services.yml:</p>
  
  <pre><code>    assetic.filter.csslint:
      class: IOKI\CommonBundle\Assetic\Filter\CssLintFilter
      tags:
          - { name: assetic.filter, alias: csslint}
  </code></pre>
  
  <p>config.yml</p>
  
  <pre><code>assetic:
      filters:
          csslint:
              resource: %kernel.root_dir%/../src/Project/CommonBundle/Resources/config/services.yml
  </code></pre>