Make ProductItems not rerender unecessarilly

[blimpich]

there is a performance problem introduced by fixing #258 that can't be fixed without rebuilding product items, which is that every time anything happens in a form, including just typing a character into the notes field, then the entire list of product items gets rerendered, this works for making sure errors show up. You could make it a pure component or implement a shouldcomponentupdate method but the problem is that the state logic is controlled by antD's form HOC and subcomponents, which I haven't implemented to the letter and am using a janky way of making it work, so the behavior is off. I would need to redo forms to work with how antd intended for it to work in order to get the purecomponent to work correctly. This is fairly low priority though since the only bad part about this is that if there happens to be a lot of ship items then you can't type as quickly as you would like in the note field section, which isn't even used that often so not super important as of right now.