Add an IsFolder method to FileOrFolderInformation class. (#207)

            [DataMember(Name = "FileSize")]

            public long SizeInBytes { get; private set; }

            /// <summary>

            /// Gets whether the current item is a folder by checking for FILE_ATTRIBUTE_DIRECTORY

            /// See https://msdn.microsoft.com/en-us/library/windows/desktop/gg258117(v=vs.85).aspx

            /// </summary>

            public bool IsFolder { get { return (this.Type & 0x10) == 0x10; } }

            /// <summary>

            /// Overridden ToString method providing a user readable

            /// display of a file or folder. Tries to match the formatting

                DateTime timestamp = DateTime.FromFileTime(this.DateCreated);

                // Check if this is a folder.

                if (!string.Equals(this.SubPath, this.CurrentDir))

                if (this.IsFolder)

                {

                    return string.Format("{0,-24:MM/dd/yyyy  HH:mm tt}{1,-14} {2}\n", timestamp, "<DIR>", this.Name);

                }