Wiki header changes

These changes were specified over in #2 (closed) We'll need to deploy this with ansible after it has been merged.

It doesn't look like the wiki project was set up with sass compilation. So I made the small header spacing changes to theme/assets/sass/style.scss and then ran: sass --style compressed theme/assets/sass/style.scss > theme/assets/css/style.css manually. I guess the original creators of the wiki site went with a metalsmith theme and didn't need to tweak the sass/css?