1.2.0

• New methods on Menu:
  • submenu for submenus with optional headers
  • void and voidIf for empty list items
  • wrap to wrap the menu in an html tag with optional attributes
  • A blueprint method to copy the menu without it's contents
  • Html item convenience methods: addItemClass, setItemAttribute
  • Html parent convenience methods: addItemParentClass, setItemParentAttribute
• Added HasHtmlAttributes and HasParentAttributes interfaces
• HtmlAttributes and ParentAttributes now also have a setAttributes method