Analyze exchange performance

Do analysis of exchange tab (market CNY_BTS).

What happens when we load the page?

- how many subscriptions do we end up with? (in ChainStore)
- how often are we re-rendering, and which component? (profiling)

Useful links
- https://blog.logrocket.com/make-react-fast-again-part-3-highlighting-component-updates-6119e45e6833/
- https://reactjs.org/docs/optimizing-performance.html
- https://reactjs.org/docs/perf.html

At the end we want to reduce re-renders such that each component is only rendered once, after data is loaded properly.