Contacts: Implement CSRF prevention.

apps/contacts/ajax/activation.php

apps/contacts/ajax/addcontact.php

apps/contacts/ajax/addproperty.php

apps/contacts/ajax/createaddressbook.php

apps/contacts/ajax/cropphoto.php

apps/contacts/ajax/deletebook.php

apps/contacts/ajax/deletecard.php

apps/contacts/ajax/deleteproperty.php

apps/contacts/ajax/oc_photo.php

apps/contacts/ajax/savecrop.php

apps/contacts/ajax/saveproperty.php

apps/contacts/ajax/updateaddressbook.php

apps/contacts/ajax/uploadimport.php

apps/contacts/ajax/uploadphoto.php

apps/contacts/js/contacts.js

apps/contacts/templates/part.contact.php

apps/contacts/templates/part.cropphoto.php

core/templates/layout.user.php