Constant ptree::print_config::UTF_CHARS

pub const UTF_CHARS: StaticIndentChars = StaticIndentChars{down_and_right: "├",
                  down: "│",
                  turn_right: "└",
                  right: "─",
                  empty: " ",}

UTF-8 indentation characters, using regular box-drawing characters

This is the character used in the Linux command tree.