API REVIEW request for RT17668 Disable/enable tabs in a TabPane

[Kinsley Wong]

JIRA: http://javafx-jira.kenai.com/browse/RT-17668

This tweak will add the following api to Tab

     public final void setDisable(boolean value);
     public final boolean isDisable();

     /**
      * Sets the disabled state of this tab. Setting
      * disable to true will cause this tab and the tab content to
      * become disabled.
      *
      * @defaultValue false
      */
     public final BooleanProperty disableProperty();