Only display result_section divs when results exists.

Should make the styling more straightforward.
Add 'p' tag

Makes styling easier.
Add responsive styling conditional to attachment display
First attempt responsive framework.

Key styles retained.
Changes to locale switcher on mobile

Now part of global navigation, sits within the main menu on mobile
Removed un-needed HTML and CSS

Conflicts:

    app/assets/stylesheets/responsive/_header_layout.scss