'make help menu more readable'

def print_topics(self, header, cmds, cmdlen, maxcol):

    if cmds:
        self.stdout.write(header)
        self.stdout.write('\n')
        if self.ruler:
            self.stdout.write((self.ruler * len(header)))
            self.stdout.write('\n')
        for cmd in cmds:
            help_msg = getattr(self, 'do_{}'.format(cmd)).__doc__
            self.stdout.write('{:<16}'.format(cmd))
            self.stdout.write(help_msg)
            self.stdout.write('\n')
        self.stdout.write('\n')
