Quote yes-no locales

Yes/no are yaml reserved words and they are evaluated as boolean values
Merge pull request #616 from moneyadviceservice/bug/yes-no-translations

Quote yes-no locales
Adding markup and copy to sign in
Fixing sign in layout
Merge branch 'sign_in'
Fix case on sign in titles
Set the timezone so the opening hours respects BST
Add chat concern
Add chat behavior