Issue 65 fix: Added eio query string

Tell me if this isn't what you intended and/or if there's anything else I need to do.

Basically I added a eio parameter to this.query that takes the version number from engine.io-parser (see Albert's pull request). Also changed Socket.protocol to take that same protocol version.

Note that you have to integrate Albert's changes to engine.io-protocol/parser, otherwise mine won't work.