bl tests are failing on node v5.6.0 because of nodejs/node#4951. What is failing is appending multiple buffer list within themselves: https://github.com/rvagg/bl/blob/master/test/test.js#L79-L94.

I am not sure we were relying on some broken functionality of core (not checking if arguments were buffers). In fact, the only thing of Buffer is relying on is a copy method.

Not sure what is the best fix for this, either on node or here.

Also reported here: moscajs/mosca#412.

cc @rvagg