Configuration file framework

* A framework for YAML configuration files using SnakeYAML was added.
The paths used may contain dots, representing sub-sections.
* Added OperatingSystem methods for getting the user's home directory,
as well as the AppData directory
* Added OperatingSystem.findResource(String) to get a URL to some
resource, supports fake "included://" protocol for getting in-jar files
* launch(File) method moved to OperatingSystem