(js) Improve confirm dialogs for deletions

UI/WebServerResources/js/Contacts/AddressBookController.js

@@ -89,7 +89,8 @@
     
     function confirmDeleteSelectedCards() {
       Dialog.confirm(l('Warning'),
-                     l('Are you sure you want to delete the selected contacts?'))
+                     l('Are you sure you want to delete the selected contacts?'),
+                     { ok: l('Delete') })
         .then(function() {
           // User confirmed the deletion
           var selectedCards = _.filter(vm.selectedFolder.cards, function(card) { return card.selected; });

UI/WebServerResources/js/Contacts/AddressBooksController.js

@@ -97,7 +97,8 @@
       }
       else {
         Dialog.confirm(l('Warning'), l('Are you sure you want to delete the addressbook <em>%{0}</em>?',
-                                       vm.service.selectedFolder.name))
+                                       vm.service.selectedFolder.name),
+                       { ok: l('Delete') })
           .then(function() {
             return vm.service.selectedFolder.$delete();
           })

UI/WebServerResources/js/Contacts/CardController.js

@@ -121,7 +121,7 @@
     function confirmDelete(card) {
       Dialog.confirm(l('Warning'),
                      l('Are you sure you want to delete the card of %{0}?', card.$fullname()),
-                     {ok: l('Yes'), cancel: l('No')})
+                     { ok: l('Delete') })
         .then(function() {
           // User confirmed the deletion
           card.$delete()