MAJOR FILESYSTEM BREAKING CHANGES:

> normalizing a folder path is now guaranteed to return a path ending with '/'
> isRootOrParent now checks for './' and '../' instead of '.' and '..'
> added expandUserPath, which expands the '~' character to the user's home path

* NEEDS DOCUMENTATION
* NEEDS WIN32 TESTING
* NEEDS CLEANUP (especially Internal/ScanHelper)