fix a bug that market.php crashes when the user has not logged in

Signed-off-by: Takashiro <takashiro@qq.com>
disable anonymous users to select quantity-limited prices

Signed-off-by: Takashiro <takashiro@qq.com>
add a new selection (delivery time) on shopping cart

Signed-off-by: Takashiro <takashiro@qq.com>