Introduce websocket for some updates from the server

[gomoripeti]

Some of the REST endpoints (that are currently polled by the front end) could be replaced by websocket notifications from the server:

these definitely as they usually don't return new info

• "api/trace_status"
• "api/mon_get_all"

maybe these too:

• "api/capture_data"
• "api/data"

[afronski]

I would add to it a small finding (not confirmed yet for 100%) - due to setTimeout and setState interleaved calls we are building up memory (plus consuming a lot of CPU for each frame) which sometimes leads to Aw snap! in Google Chrome and crashed tab.

My suggestion would be to stick to requestAnimationFrame (leveraging virtual DOM and React) and WS connection, and provide updates in more event-base fashion.