Lab 9: Linear Categoriser
    
       - Build a system that learns a linear classifier given data.
 
       - Make a new java project.
 
       - Put in an array of 2D points in two categories; the category can be
	   represented by a third integer point. 
 
       - Make a line that separates them.  Remember, a line can be
	 represented many ways including by two points, and by the equation
         x=my+b (where m is the slope constant and b is the offset from
         the origin).
 
       - In response to data, move the line. You can try the perceptron
       learning rule, or just move it gradually.
 
       - Try it with this data file.
 
       - Try it with this data file.
 
       - Can you make a plane for 3D?