Some documentation fixups

In the process of going through the chapters, I noticed a few places where textual improvements could be made (and a couple of minor bugs).  I've sliced the changes very finely, so please let me know if I should merge some of them together, or if they can be improved in some way.  Some of the changes are really only recommendations for slight modifications to the textual flow, so you might not need all of the commits.  Hopefully this helps out in some way!