Adds pull quote and updates heading styles

- pull quote: https://himedlooff.github.io/cf-typography/docs/#pull-quote
- heading style updates
 - automatically adds the bold and italic overrides for h1, h2, and h3 since they are commonly used for styling blocks of various text
 - moved webfonts and top margins to each heading declaration instead of jamming them together; this makes the styles a little easier to read