[#35] Valid contact form now redirected

* Rather than rendering a success page
  in the same action as the contact form,
  the action now redirects to another
  action (contactSuccessAction) to prevent
  users from resubmitting the form and
  spamming me with email.
Merge branch 'task-35-make_contact_success_forwarded_in_controller' into develop
Merge branch 'develop'