Lots of minor fixes

I went into obsessive compulsive mode.  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
Merge pull request #17 from kablamo/minor-fixups

Lots of minor fixes