App::Pebble::Helpers::DateTime - DateTime helpers.
Support DateTime objects "natively" by making sure they TO_JSON-ify properly, and provide some useful helper methods.
Round off the datetime $to_unit ( "year" | "month" | "day" | "hour" | "minute" | "second" ) by setting the smaller units to 0 (e.g. minutes) or 1 (e.g. month).
Change the object in-place.
Note: This could be ported into DateTime proper. It's just here for now to provide a convenience function.