ZigZag Algorithm in a Grid (revised version, 2.1)

This four year old project has had a new update. The original intention was to illuminate the serialization of a two-dimensional array into a one-dimensional array. This is often done through the JPEG (or MJPG) libraries. My project (or app-demo) now implements something further, (other than the 'ZigZag'-routine): 'RowMajor', 'ColumnMajor', 'Random', 'Circular', and 'DiagonalUp'.