Replace Pandoc with Kramdown and wkhtmltopdf

* Use Kramdown to generate HTML from Markdown.
  * Update HTML template.
  * Note that we no longer get sections.
    * IDs are now on headings.
* Use wkhtmltopdf to generate PDF from HTML.
* Don't generate ODT format any more.
  * Had reported compatibility issues with Microsoft Word.
* Formatting changes.
  * Float physical address in header to the right.
  * Add a page break before Professional Experience section.