Large Font Release

*Added extensive controls in the theme customizer that allow users to
pick both font sizes and font families.
*Synced theme with recent updates to the _s framework.
*Cleaned up a lot of CSS that was in the way when customizing fonts.
*Improved CSS for the new version of Featured Articles. Fixed issue that
was causing large gaps when post titles wrapped. Like elsewhere, users
can now control the font sizes and font families for the plugin in the
customizer.
*Fixed issue in the post editor where the screen flickered when you
clicked in the editor and CSS styles were applied. The editor is much
more likely now to display exactly like posts on the front-end.