Fixing issue with HK--en lookup-key creation and validation.

 Fixing subkey creation for addresses with an acceptable language specified. Also fixing validation to work properly for these addresses. This affects places like Hong Kong, which has both English and Chinese data.

Added test data and tests to expose the issue.

Also changing the build file to show output when running tests so when they hang because of a null-pointer exception this reaches the command line! Made debugging the tests much easier.
Above you canonicalize currentFullKey because you assume that id (without sublevel) can have a --language suffix already. I think you have to canonicalize the key here too before making the dataSource lookup.