support array to_ng_int
add order and its items resource.
support array to_ng_int
fixed update event error: slug is nil
update db schema.
add alipay gem.
add alipay config.[SETTINGS CONFIG WAS MODIFIED]
support array to_ng_int
create order.
add pay button.
update order db schema.
handle alipay return and notify request.
add test for alipay return and notify request.
decrement event tickets_quantity when order create.
add orders javascript test.
add order feature test.
create order should have items.
create order after use logined.
fixed rspec error.
merge master.