Correct file and (re)source mapping to work the same on *nix and Windows platforms

The file and (r)esource mapping has been largely abstracted through java.nio.file.Path.
However this mapping needs to be serparated between the actual file/folder paths which needs to handle differently between *nix (using "/") and Windows (using "
"), and the relative (re)source paths which are defined in and through yaml.
For the latter we always use and only support the *nix type "/" as path separator.