Order page elements consistently with other pages.

'right_column' appears after content it will be to the right hand side
of on other pages. It doesn't matter to the current stylesheet, which
floats it anyway, but is easier to handle in responsive css if the
markup is consistent.
Remove the quote from a comment in request correspondence.

It gets hidden by the current stylesheet, so easier and more efficient
not to render it at all.
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 at responsive header.
Add styling for popups
Add frontpage styling
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
removed grid-column(12) from #container

(I don't *think* it's needed here and adds extra padding)
remove pseudo-centring from form button
removed border radius, button will now appear as native style
tweaked grid layout code to give uniform appearance
font-weight now bold, 700 was hangover from web fonts which are no londer used
set up sensible global CSS styles
set up sensible global CSS styles
set up front page with sensible defaults
sensible default styling for definition lists
refactored and simplified the navigation layout