fails:CGI::HtmlExtension#html when passed no arguments includes the passed block when passed a block
fails:CGI::HtmlExtension#html when passed 'PRETTY' includes the passed block when passed a block
fails:CGI::HtmlExtension#html when each HTML generation returns the doctype declaration for HTML3
fails:CGI::HtmlExtension#html when each HTML generation returns the doctype declaration for HTML4
fails:CGI::HtmlExtension#html when each HTML generation returns the doctype declaration for the Transitional version of HTML4
