Update lib/Icecave/Chrono/Support/Calendar.php
Merge pull request #12 from koden-km/patch-1

Update lib/Icecave/Chrono/Support/Calendar.php
Added Time::on() and Date::at() [#11]
Style fix
Style fix on test suite.
Implemented DateTime::date() and ::time() [#11]
Implemented string formatting system (fixes #13, started on #14)
Updated the readme with some terminology and a basic example (#18) [ci skip]
Minor readme fixes [ci skip]
Minor readme fixes [ci skip]
Minor readme fixes [ci skip]
Minor readme fixes [ci skip]
Updated typhoon validators.
Added FormatterInterface::escape() [fixes #20]
Added 'T' to ISO format for date times.
Added Time::totalSeconds()
Added Ordinal support class.
Added doomsday/iso week date utilities to Calendar.
Implemented DefaultFormatter::formatDateTime(), does not support e or T yet [#14]