Things now seem to work on EdgeCast, Wowza, and nginx-rtmp-module.

To make things work, I had to keep track of the command that was sent for each
packet ids. That way, when the server calls does a _result() invoke, we can see which state we are in. This is more reliable than the assumptions made with the simplistic FSA implementation that existed before.

Furthermore, we needed to handle the _onStatus() invoke properly, to ensure
that we don't start streaming before the server tells us
"NetStream.Publish.Start".

I pulled from upstream master before submitting this pull request and after testing all three servers again.