Wrap files at <80 characters to resolve #17.
Add selected class to demo list item.
Updated link paths and re-add comment to demo section.
Trailing slashes and absolute paths for buttons on the first page.
Reverted/Fixed page titles.
Eliminate extra whitespace, move all code samples to the first column.
Merge pull request #22 from brianhall/master

Wrap files at <80 characters to resolve #17.
Update 06-ch04-directive.html
Update 06-ch04-directive.html