main: fix the damn header

main/static/main/css/pattern-scaffolding.css

main/static/main/css/styles.css

...ain/images/background-images/50632006293_2001701fa0_o.jpg

main/static/main/images/background-images/bartos-2.jpg

...tatic/main/images/background-images/bartos-newsletter.png

main/styleguide/source/_patterns/organisms/header.mustache

main/templates/main/blocks/articles_timeline_block.html

main/templates/main/includes/layout/header.html