Adds a new locale for Indonesian language support

This is a bugfix for issue 'IsSame() and similar functions #40'.

This release has a bugfix for StartOf("isoWeek").

This release is mainly to address a fix for supporting parsing timestamps with a Z timezone marker. There is also a few small changes to add getting month names by number, or weekdays in a locale aware order. See CHANGELOG.md for list of all updates.

This release is all about supporting weeks! After adding locales, supporting locale-aware weeks, weekyears, and weekdays was a glaring omission. This release adds support for the getter/setter methods, and adds tokens for parsing and formatting of weeks, weekyears, & weekdays. Check the CHANGELOG.md for more information.

Added the ability to specify a locale when parsing a datetime string. Please see CHANGELOG.md for more information.

Added support for a new formatting token 'zzzz' to display the full timezone name. Using the library https://github.com/tkuchiki/go-timezone to support this functionality.

Support for internationalization using locales. Can only be used in formatting functions currently. Initial supported locales are en, es & fr.