This patch:
- introduces Request class.
- implements Page.setRequestInterceptor method. The method
allows to install a callback which will be called for every request
with a |Request| object as a single parameter. The callback is free
to override certain request's properties and then either continue or
abort it.
- implements request interception api for phantom-shim and unskips the
module/webpage/abort-network-request.js phantomjs test
References #1
