[nice to have] Load open orders

[anxolin]

The swap UI keeps track of the open orders, and notify when they are executed.

The open orders and recent orders are saved in the local storage.This implies that they won't be seen in a different browser.
One improvement could be to use the API to load the orders. This would allow a better UX and multi-browser experience

Ideally we would leverage what we have. It's nice to show the orders persisted in the browsers in case the API fails, or while the API is giving us the open/recent orders.

[elena-zh]

related to #1334