Implemented templating using mustache templates
	Added sample mustache template files that generate a specific changelog format.
	Migrated source to the Maven build system.
	Changelog issues are now displayed sorted by issue type when using the module changelog, otherwise they are displayed as normal (file changelog).
	Fixed and added new Javadoc.
	Added a basic test case for testing the changelog templating.
	NOTE: the JQL string argument  may require use of '_' for spaces and '[' and ']' for quotation marks (due to how Maven handles quotation marks).