Fixes conformance about JS URI in links

In PhantomJS, javascript inside URIs are executed asynchronously when
a click is made on the element. This is not the case in Gecko.
So we should wait a bit after the execution before continuing.
This is a dirty hack but we have no choice for the moment.
Added webpage.__type

toString on a webpage object indicates qtruntimeobject in PhantomJS.
This new property is an alternate way to know if the
object is a webpage object.
Implements webpage.objectName and webserver.objectName

These properties exist in the PhantomJS implementation
Make SlimerJS compatible with Gecko 24
nuts...