Header line
Update pdflatex and xelatex pandoc templates to use YAML metadata block. Like this:

---
title: An Article About Something
author:
- name: Kieran Healy
  affiliation: Duke University
  email: kjhealy@soc.duke.edu
date: February 2014
abstract: Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enimad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.
...