title: //a[@class="post-title"]/text()
title: //meta[@name="twitter:title"]/@content
body: //img[@class="img-responsive img-comic"]
author: string('Scott Adams')
date: //meta[@property="article:publish_date"]/@content

test_url: http://dilbert.com/blog/entry/death_by_hypnosis_or_not/
test_url: http://dilbert.com/strips/comic/2013-10-22
test_url: http://feed.dilbert.com/dilbert/daily_strip