Check nanosecond in the various tests, and add tests for truncating to the second.
Check nanosecond in the various tests, and add tests for truncating to the second.

chansen/DateTime.pm,1nickt/DateTime.pm,1nickt/DateTime.pm,chansen/DateTime.pm,1nickt/DateTime.pm,autarch/DateTime.pm,autarch/DateTime.pm,chansen/DateTime.pm