Hover states and colours on primary and info buttons.
Merge pull request #153 from theodi/static_pages_markup

New homepage copy, titles on About and Contact pages.
New homepage copy re-added into en.yml instead of statically.
Apostrophe fixes on homepage copy.
Proper styles for homepage video text/links and new footer design.
Footer logo added.
Merge pull request #157 from theodi/static_pages_markup

New homepage copy re-added into en.yml instead of statically.
Moving start-cert-modal container to the application layout (so it's available on other pages), and adding a close button.