Feature/midi port form webkit upgrade

@soulfresh I was able to upgrade to Node Webkit v0.8.5. We're stuck there right now since v0.9.0 makes the switch to Node v0.11.9. We aren't able to run Node 11 yet because node-midi doesn't support it.  See here: https://github.com/justinlatimer/node-midi/pull/52

The app loads in this branch based off of your midi-port-form branch except there's sometimes a crash when you try to add the midi port. I'm not sure if this is new or not.

Btw, this branch works in Node v0.10.29