Convert py tests

This replaces the issue #39 pull request

All additions are files in test
test_argparse_mocha.js - mocha test cases derived from test_argparse.py

These files might be handy if we want to extract more tests, or generate them in different form.
Being development code they might not belong in the test directory
test_argparse.py  - Python original
test_argparse_convert.py - JSON serializes the tests that it can (76 'classes')
test_argparse.coffee - writes mocha test from the JSON object