Print the subcommand part of the help.

def print_subcommands(self):
        """Print the subcommand part of the help."""
        lines = ["Call"]
        lines.append('-'*len(lines[-1]))
        lines.append('')
        lines.append("> jhubctl <subcommand> <resource-type> <resource-name>")
        lines.append('')
        lines.append("Subcommands")
        lines.append('-'*len(lines[-1]))
        lines.append('')

        for name, subcommand in self.subcommands.items():
            lines.append(name)
            lines.append(indent(subcommand[1]))

        lines.append('')
        print(os.linesep.join(lines))