This class can draw a graphic of a circular gauge like the cars fuel gauge with a pointer that indicates the current position of a given parameter value relative to given scale.
By default it uses a scale from 0% to 100% and draws a red arc at 50% a yellow arc at 80% and a green arc at 100%. It is also posible to show a small legend in the gauge.
Currently it generates a PNG image with the fixed size of 100 x 100 points.