HTML::Formatter is a base class for classes that take HTML and format
    it to some output format. When you take an object of such a base class
    and call $formatter-format( $tree )> with an HTML::TreeBuilder (or
    HTML::Element) object, they return the appropriately formatted string
    for the input HTML.

    HTML formatters are able to format a HTML syntax tree into various
    printable formats. Different formatters produce output for different
    output media. Common for all formatters are that they will return the
    formatted output when the format() method is called. The format()
    method takes a HTML::Element object (usually the HTML::TreeBuilder root
    object) as parameter.
