Add class to clear feedback form on whitehall

This is to clear the toggle link from stick-at-top content.
Merge pull request #272 from alphagov/feedback-fix

Add class to clear feedback form on whitehall
Remove padding from OGL in footer at small sizes

The padding-left is required on big screens, but displays strangely on
mobile.
Merge pull request #274 from alphagov/bugfix-ogl-logo-small-screen-padding

Remove padding-left from OGL in footer at small sizes
Merge branch 'master' of github.com:alphagov/static
Merge branch 'master' into callout-killer