Minimal sample React implementation

[hmuurine]

Summary

This PR implements a minimal React build and a minimal React wrapper component for the Pixel Streaming library. The wrapper component starts a Pixel Streaming session on component mount and disconnects on component unmount. This allows it to be used as part of a single page app, where the user can navigate between a Pixel Streaming view and other views.

Test plan

• started Signalling server and a sample UE Pixel Streaming application
• ran npm run build-all and npm run serve-prod for the React sample application
• navigated to localhost:8080 and verified that the sample application started and was able to connect to the UE app

Screen.Recording.2023-03-17.at.9.42.22.mp4

• ran npm run build-dev-all and npm run serve and verified that also the dev build with source maps worked as expected

[lukehb]

This a great resource and starting point for people wanting to build a react based Pixel Streaming experience. Merging!