Trapping focus
Merge branch 'master' of https://github.com/Defra/capd-styleguide

* 'master' of https://github.com/Defra/capd-styleguide:
  Lower alpha list added. Removed opens in a new window span for accessibility which is no longer required
  Removed validation summary and validation blocks negative margin due to alignment issues
  Modified JS to prevent collapsible function running if inside language markup class
  Removed reference to transitions and visual effects
  Modifications made to dialog styling suggested by Tim Paul