Convert reST to PDF using rst2pdf (which converts from rst to PDF
using the ReportLab open-source library).
rst2pdf(input, command = "rst2pdf", options = "")the input rst file
a character string which gives the path of the
rst2pdf program (if it is not in PATH, the full path has to be
given)
extra command line options, e.g. '-v'
An input file *.rst will produce *.pdf and this output
filename is returned if the conversion was successful.