Images: Book 3 Chapter 8 onwards: Need to update Cornell box screenshots

[jammm]

Since the bug in random_cosine_direction was fixed, the screenshots from figure 8-1 are outdated. RayTracing/TheRestOfYourLife#8

[hollasch]

Also note that the initial Cornell box render is incorrect, since the back sides of the unrotated faces should not be hit.

[hollasch]

Covered individually:

• Update render 3.03 #591
• Update render 3.04 #592
• Update render 3.05 #593
• Update render 3.06 #594
• Update render 3.07 #595
• Update render 3.08 #596
• Update render 3.09 #597
• Update render 3.10 #598
• Update render 3.11 #599
• Update render 3.12 #600