Added complementary task that showcases compilation to formats like PDF, odt, docx, etc.

Hi,

I added a complementary task that showcases how a compilation could be done for formats like PDFs, odt, docx, etc. for which Pandoc does not write to stdout, so that the `-o` option has to be used.

The task I wrote is for a compilation of Markdown files to PDFs (which is probably one of the more common cases).

I tested it on Linux with Pandoc 1.12.3.3 and Texlive (2013.20130722-1 from the Ubuntu repositories)  and it seems to work.