Description:
------------
This function is no longer defined, running it results in:

Call to undefined method tidy::isHtml()

Seeing as tidy::isXhtml() is not implemented yet and always returns false - i'm a bit stuck!

Reproduce code:
---------------
$response = $this->getResponse();
		$tidycf = array(
					   'indent'         => true,
					   'output-xhtml'   => true,
					   'char-encoding' => 'utf8',
					   'wrap'           => 200);
		
		// Tidy
		if (!$response->isException()) {
			$tidy = new tidy;
			$tidy->parseString($response, $tidycf, 'utf8');
			
			if ($tidy->isHtml()) {
				$tidy->cleanRepair();
				$this->getResponse()->clearBody();
				echo $tidy;
			} else {
				$this->getResponse()->appendBody("This Page Was Not Cleaned By Tidy\n");
				}
			}
		}

Expected result:
----------------
Anything that isnt HTML being passed from the $reponse object should have a string appended to it, any HTML should be cleaned by the tidy library.

Actual result:
--------------
Fatal error: Call to undefined method tidy::isHtml()