@Override protected void invalidated() {
                    final double ANGLE = get();
                    if (ANGLE < 0 || ANGLE > 360 ) set(clamp(0.0, 360.0, ANGLE));
                    fireTileEvent(RECALC_EVENT);
                }
Defines the angle in degree that defines the start of the scale with
it's minValue in a radial tile. If set to 0 the scale will start at
the bottom center and the direction of counting is mathematical correct
counter-clockwise.
Means if you would like to start the scale on the left side in the
middle of the tile height the startAngle should be set to 270 degrees.

@param ANGLE
src/main/java/eu/hansolo/tilesfx/Tile.java