Lots of minor fixes

Sorry I didn't break this into smaller commits.  I hope this pull request is not too crazy for you.  I went into obsessive compulsive mode and tried to think about this like a book editor or a designer or something.  Its possible I went overboard. 

I really like your cheat sheet (or else I wouldn't bother with a pull request).  So most of the changes are very minor formatting issues.  In a few places I changed the wording slightly but mostly that was only done to be consistent.

Here are the guidelines I tried to follow:
 - be as concise as possible while still being clear
 - do not omit articles like 'the' and 'a'
 - be consistent between sections
 - be consistent between command descriptions
 - section titles have only the first word capitalized