title: How to use custom Annotation Processors with Buck?
body: <p>As the title states - I'd like use custom Java Annotation Processors with Buck (e.g. Dagger 1 / 2). Checking out the documentation did not reveal any evident annotation-processing related properties for any Java (or Android) related build rules, and I also couldn't find any examples for this scenario.</p>
  
  <p>I did find <a href="https://github.com/facebook/buck/issues/85" rel="nofollow">this issue thread</a> on GitHub though, without any meaningful recent answers.</p>
  
  <p>Is this something that Buck still does not support?
  In case not, did anyone find a workaround for this?</p>