Add query string support

[shawnbot]

This PR adds support for query string parameters in the URL. It introduces a query property on Router instances that stores the last parsed query string, e.g.:

var router = new Router({
  '/foo': function() {
    assert.deepEqual(this.query, {bar: 'baz', qux: true});
  }
});
router.init();
router.setRoute('/foo?bar=baz&qux');

If the path doesn't include a ?, then this.query === null.

I've included a very rudimentary query string parser in Router.prototype.parseQuery that handles the most common forms of query string parameters:

• x parses to {x: true}
• x=y parses to {x: 'y'}
• x==y parses to {x: '=y'}
• x=1&x=2 parses to {x: ['1', 2']}

I wanted to run this by y'all before I dive into the server side of things, but the basic browser tests that I've added pass. Thoughts?

[shawnbot]

Eh, looks like this isn't going to get merged. Closing.