Use of logging in example code

[ashander]

as pointed out in #52 using standard modules makes things easier on users. (but perhaps harder on us?)

[hyanwong]

Jerome uses import logging in his code, and I think it makes things easier to read / program too. He uses:

log_level = logging.WARNING
if args.verbosity == 1:
    log_level = logging.INFO
if args.verbosity >= 2:
    log_level = logging.DEBUG
logging.basicConfig(
    format='%(asctime)s %(message)s', level=log_level, stream=sys.stdout)

(I guess you could use stream=args.logfile with

parser.add_argument("-g","--logfile", dest="logfile", type=argparse.FileType('r'), default='-', help="name of log file (or '-' for stdout)")

then

logging.debug("Some internal stuff")
logging.info("Message")
logging.warning("Something's wrong")