title: Protocol buffer3 and json
body: <p>Protocol buffer v3 claims, that library is json friendly (<a href="https://developers.google.com/protocol-buffers/docs/proto3#json" rel="noreferrer">https://developers.google.com/protocol-buffers/docs/proto3#json</a>), but I cannot find how to achieve get that mapping. Should I add some plugin, or some option into protoc, or call something special instead SerializeTo/ParseFrom?</p>
  
  <p>Is it someone who use that feature?</p>