function Misc_FileExt($FileOrExt) {
		$p = strrpos($FileOrExt, '.');
		$ext = ($p===false) ? $FileOrExt : substr($FileOrExt, $p+1);
		$ext = strtolower($ext);
		return $ext;
	}
function Misc_FileExt($FileOrExt) {
		$p = strrpos($FileOrExt, '.');
		$ext = ($p===false) ? $FileOrExt : substr($FileOrExt, $p+1);
		$ext = strtolower($ext);
		return $ext;
	}
Return the extension of the file, lower case and without the dot. Example: 'png'.