Add ml usage examples

MLUsageExamples contains contains small example ECL programs that illustrate how to
use the functions and macros in the Machine Learning (ML) library. Each of these
examples are stand-alone. To execute and of them, you only need the ML library in your
repository.

The number of example programs in this bundle will increase over time.

ORGANIZATION
  The folders in this bundle is organized like the ML library's folder structure. For example
  an example of how to use ML.Mat.Add will be found in the Mat folder because ML.Mat.Add.ecl
  is in the MLUsageExamples/Mat folder of the ML library. Furthermore, modules of the ML library
  will have  examples in a folder named after the module. For examples of how to use the functions
  of the ML.Mat.Each.ecl module with be found in the folder MLUsageExamples/Mat/Each.