0.3 2014-5-13
    * yamlasjson now adds extra blank lines
    * handle fenced code-blocks that do not need a handler
    * relative images handled
    * new plugins & tests for gle and gnuplot
    * documentation updated
    * now can use wkhtmltopdf to generate PDF output
0.2 2014-5-12
    * major refactor from my previous code (not released)
    * Now has plugins
    * Some documentation needs completing