Convert json to markdown.

        Takes in a .json file as input and convert it to Markdown format,
        saving the generated .png images into ./images.

def convert(self, json, fout):
        """Convert json to markdown.

        Takes in a .json file as input and convert it to Markdown format,
        saving the generated .png images into ./images.
        """
        self.build_markdown_body(json)  # create the body
        self.build_header(json['name'])  # create the md header
        self.build_output(fout)