Alert.js: buttons on alerts are now really `<button>`. Buttons can now have...

Alert.js: buttons on alerts are now really `<button>`. Buttons can now have the default focus, as specified by the `focus` attribue in the button configuration.

javascript/src/Alert.js

@@ -39,6 +39,7 @@ var QfqNS = QfqNS || {};
      *
      *   {
      *     label: <button label>,
+     *     focus: true | false,
      *     eventName: <eventname>
      *   }
      *
@@ -139,8 +140,11 @@ var QfqNS = QfqNS || {};
                 $buttons = $("<div>").addClass("alert-buttons");
             }
 
-            $buttons.append($("<a>").append(buttonConfiguration.label)
-                        .addClass("btn btn-default")
+            var focus = buttonConfiguration.focus ? buttonConfiguration.focus : false;
+
+            $buttons.append($("<button>").append(buttonConfiguration.label)
+                .attr('type', 'button')
+                .addClass("btn btn-default" + (focus ? " wants-focus" : ""))
                 .click(buttonConfiguration, this.buttonHandler.bind(this)));
         }
 
@@ -173,6 +177,7 @@ var QfqNS = QfqNS || {};
 
         $alertContainer.append(this.$alertDiv);
         this.$alertDiv.slideDown(this.fadeInDuration, this.afterFadeIn.bind(this));
+        this.$alertDiv.find(".wants-focus").focus();
         this.shown = true;