def update(object = {})
      meta_tags = object.respond_to?(:to_meta_tags) ? object.to_meta_tags : object
      @meta_tags.deep_merge! normalize_open_graph(meta_tags)
    end
def update(object = {})
      meta_tags = object.respond_to?(:to_meta_tags) ? object.to_meta_tags : object
      @meta_tags.deep_merge! normalize_open_graph(meta_tags)
    end
Recursively merges a Hash of meta tag attributes into current list.

 @param [Hash, #to_meta_tags] object Hash of meta tags (or object responding
   to #to_meta_tags and returning a hash) to merge into the current list.
 @return [Hash] result of the merge.