Changed  arparse arguement parser with Docopt

The argument parser used was Argparse,
this is replaced with Docopt arguement parser.

Docopt:http://docopt.org

Docopt(it uses only re and sys)  is  a beautiful pythonic argument parser. It allows Docstrings written as help
message to be used as template to parse arguments.

Howdoi is starting to extend and include more options,so this will be easier
on the eye and brain.