Removes TODO fixed in 3fc3bae and minor whitespace cleanup.
Add where note.
Merge pull request #11 from wting/ch1_cleanup

Removes TODO fixed in 3fc3bae and minor whitespace cleanup.
Merge pull request #12 from wting/add_where_note

Add `where` note.
Change from using "let" to use "var"
Merge branch 'master' of github.com:w7cook/AoPL
Fix to strip out extra trailing spaces, and remove Let import