Fix improper entity in NL translation

Closes #1828
Changed translation in Dutch of 'United Kingdom' to 'Verenigd Koninkrijk'. Refers to issue #1828.
Merge pull request #1834 from quintel/translations

Changed translation in Dutch of 'United Kingdom' to 'Verenigd Koninkrijk...
Fix broken predictions page

  * button_to_function has been removed from Rails.
  * Many of the CSS styles were broken.