Package tzwhere for PyPi and include schaefer0's changes

1) Packaged things for PyPi assuming a name of tzwhere (it isn't taken yet) and an MIT license to match the NodeJS version
2) Python 2.6+ includes json by default so modified the import to use that and fall back to simplejson for older versions
3) Included the changes from schaefer0's pull request that modify the argparse location so that import tzwhere works correctly