pgte/duplex-emitter — pull request #7 by Soarez (2013-07-26 18:36:45+00:00)
Title: removeAllListeners work

`removeAllListeners` doesn't work when invoked without parameters because [removeAllListeners](http://nodejs.org/api/events.html#events_emitter_removealllisteners_event) uses `arguments.length`.

Also added a test for it.