Add datagovhk

This pull request adds @datagovhk to the list of government organizations. They're doing some great open source work around data.gov.hk.

Going off of [the wikipedia entry](http://en.wikipedia.org/wiki/Hong_Kong), should Hong Kong be listed as it's own top-level category, or is China more appropriate?

(Ignore the @kentcc noise that came from running the alphabetization script before committing)