globalVariables: allow window.__phantomas
Additional check for scope.js injection
WebPage.release() is deprecated, use close() instead
phantomas.spy: add a proxy function

window.__phantomas.proxy(window.document, 'getElementById', function(id) {
	// track calls to document.getElementById
	// "original" arguments are passed to callback
});
domQueries: use phantomas.spy()

* simplify the code that "proxies" native DOM methods
* count calls to document.getElementById() and document.getElementsByClassName() as well when reporting "DOMqueries" metric