Rename figure 3.06

Author: hollasch

books/RayTracingTheRestOfYourLife.html

@@ -1057,7 +1057,8 @@
 <div class='together'>
 And plot them for free on plot.ly (a great site with 3D scatterplot support):
 
-  ![Figure [pt-uni-sphere]: Random points on the unit sphere](../images/fig.pt-uni-sphere.jpg)
+  ![Figure [rand-pts-sphere]: Random points on the unit sphere
+  ](../images/fig-3.06-rand-pts-sphere.jpg)
 
 </div>