Read and adds given file's content to data array
        that will be used to generate output

        :param filename File name to add
        :type str or unicode

def add_file(self, filename):
        """ Read and adds given file's content to data array
        that will be used to generate output

        :param filename File name to add
        :type str or unicode
        """
        with (open(filename, 'rb')) as f:
            data = f.read()
        # below won't handle the same name files
        # in different paths
        fname = os.path.basename(filename)
        self.files[fname] = base64.b64encode(data)