Add image of Glenn's orbital sunset (sunrise?)

http://kb.osu.edu/dspace/handle/1811/50485
Split the figures of page 424-425
Add image of Mercury Mission Control

http://www.nasa.gov/centers/kennedy/about/history/50thgallery/62-MA6-161.html

Not the same as in the book, but it is from the same mission. See
http://archive.org/stream/thisnewoceanhist00swen#page/425/mode/1up