Bug #16469 for Date-Holidays-AU: Small improvement patches

Hi David, It is me again - I have looked over your 0.03 release of Date::Holidays::AU. On the basis of this I came up with these small fixes: - A more general fix - I have replaced die with croak, this mean that the exception is from the callers perspective, which is good when we are talking malformed or missing parameters. This is also the general recommendation in Advanced Perl Programming and in Perl Best Practices AFAIK. The fix might be two wide and we might be interested in dying if a REAL exception occurs, but evaluate my fix and get back to me. The fix influences Date::Holidays::AU and Makefile.PL (in the latter I list Carp as a prerequisite. - The next fix is in Date::Holidays::AU, instead of checking for existance of keys in holidays, just check for whether they are defined, this gives a more flexible API. I for one can call holidays with undef in the state and the fallback to 'VIC' works. About the default I have added a warning - remove it if it annoys you. The fix influences Date::Holidays::AU - The last fix is in the regex checking year, I have made the same change, removed the check for existance of the key and just check for definition - and I have improved the regex to ask for a 4 digit year - would be an idea to default to current year if not provided with year? The fix influences Date::Holidays::AU - Finally I have added some more tests to check some of the fixes mentioned above. The fix influences t/test.t Hope you can use it - let me know if you have any questions or problems. Thanks for you swift release of 0.03 - I am getting ready with my next release of Date::Holidays. jonasbn