DateTime

Changes for version 0.07

IMPROVEMENTS
- Added a small hack to the compare() method so that this module can be used with Set::Infinite.
- Changed compare so that it can be used to compare two objects from different calendars that conform to the DateTime::Calendar interface.
- Added explanation of exactly what calendar this module represents ("proleptic Gregorian calendar") to docs.
- Added a Spanish language DateTime::Language subclass. Implemented by Flavio S. Glock.
- Added support for specifying a language by ISO code ("en" or "pt-br") as well as the subclass name. Based on a patch from Erich Cholet.
- Revamped the externally visible DateTime::Language API.
- Objects created via the from_object() method are set to the time zone of the object from which they were created, if it has one, or UTC otherwise.
BUG FIXES
- The from_object() method was broken because it retrieved a UTC datetime from the object passed in, and then created a new DateTime object using that UTC time as a _local_ time.
BACKWARDS INCOMPATIBILITIES
- Removed stringification overloading. Having this in place made it impossible to create a strack trace in much of the time zone code.
- Renamed the DateTime::Language->subclasses method as languages.
- It is no longer possible to directly instantiate a DateTime::Language subclass, instead use:
  - my $en = DateTime::Language->new( language => 'English' );
- The from_object() method no longer accepts a "time_zone" parameter.