Add class for footnotes
Use the golden ratio

Choosing 18px as a good base, use the golden ratio (1.618) to determine
correct line height and page width (Bootstrap's span9 is the closest
match)
Add table styling
Style for blockquotes
Move typography rules into their own section
Better hx heading rules
Styling for lists
Address styling
Tweaks to headings
Add a note about golden ratio
Merge pull request #6 from philwareham/master

Start applying the golden ration, since this is a typographical theme