[Bf-docboard] automated screenshots

[Luke Stodola]

It seems it will be a lot of needless work to keep making screenshots 
manually.  Can't we instead store the .blend files for the scene, along 
with the coords of where it should be cropped, and have a program go 
through and update them for each release?  That way we also get full 
color versions for the web and PDF, and can make a high-contrast version 
(using Blender themes?) available for the 2 color printing in the book.