Alias:

--------------------------------------------------------------------------
   Computes the fundamental alias of a frequency.

   Since version 1.
--------------------------------------------------------------------------
   Form:
   w = Alias( w, ws )
--------------------------------------------------------------------------

   ------
   Inputs
   ------
   w            (1,:)  Frequency w > ws/2
   ws           (1,1)  Sampling frequency

   -------
   Outputs
   -------
   w            (1,:)  Fundamental alias

--------------------------------------------------------------------------