use _query instead of query, closes #203

[yocontra]

fixes compat with restify and all other things that already use the req.query attribute

[yocontra]

Related: #203

[rauchg]

The requests that engine.io captures shouldn't have been touched by restify, right? So why would there be a collision ?

[yocontra]

@guille

restify overrides the http IncomingMessage prototype and tacks on a bunch of stuff

Specifically this https://github.com/mcavage/node-restify/blob/master/lib/request.js#L176 was causing the breakage.

Unrelated but this was also an issue: https://github.com/mcavage/node-restify/blob/master/lib/server.js#L250

It seems like they manually whitelisted socket.io to ignore from their stuff. Polling requests for engine.io were still ending up in their routing system where it was adding headers and generally being shitty. I was able to get around this by binding directly to the internal http server within restify. Open issue is at restify/node-restify#575

[rauchg]

I don't mind having req._query.