Refactor sign out button to a proper form so it can handle redirects
Logout follow-up

 * Removed oae.api.authentication.logout function
 * Changed sign out button in the admin ui
Replace api.logout with logout form/button in the terms and conditions widget
Merge pull request #3768 from simong/cas-logout

Refactor sign out button to a proper form so it can handle redirects
Merge branch 'master' of https://github.com/oaeproject/3akai-ux