kappy/DateTimeExtensions — pull request #26 by snoopydo (2012-10-05 07:56:21+00:00)
Title: en-NZ Holidays

Some holidays are 'Mondayised' where we also have a weekday observance.
eg New Years day, if it falls on a Saturday or Sunday then we have the following Monday/Tuesday as a holiday.

I used your suggestions via the gists in your comment, much simpler than the path I was going down.