Also, please fix the main title of the argparse section...

from
15.4. argparse<http://docs.python.org/dev/library/argparse.html#module-argparse>
—
Parser for command line options, arguments and sub-commands
to
15.4. argparse<http://docs.python.org/dev/library/argparse.html#module-argparse>
—
Parser for command-line options, arguments and sub-commands
Please note the added hyphen (-) for the word command-line. Since this is
actually one word, it needs the hyphen. This is not Python related, but is
orthology related. Please fix all this documentation imprecisions in the
section argparse. Won't take a minute.