修改ecshop商品页面自动截取详细内容作为description

修改goods.php，其他的不需要修改。

$tmpdesc = strip_tags($goods['goods_desc']);
$tmpdesc = str_replace("\n","",$tmpdesc);
/* meta */
$smarty->assign('keywords', htmlspecialchars($goods['keywords']));
if(empty($goods['goods_brief'])){
$smarty->assign('description', htmlspecialchars($goods['goods_name']).'；'.$tmpdesc);
}else{
$smarty->assign('description', htmlspecialchars($goods['goods_brief']));
}