Can I request that LoadFromFileSystemAsync allow an override to allow a enforceLowerCase bool.
At the minute NormalizeFilename forces the url to be always be lowercase.

    //
    // Summary:
    //     Puts a filename into the format /path/filename.ext (from path\FileName.EXT)
    public static string NormalizeFilename(this string str, bool enforceInitialSlash = true)
    {
        return str.NormalizeFilename(enforceInitialSlash, enforceLowerCase: true);
    }