Hardcoded API server address breaks deployment across multiple servers.

[larsgeb]

https://github.com/aaron5670/Realtime-Pub-Quiz/blob/a0a0a89dbbabb744a090bc3c9b52c60fa3dff31c/quizzer/src/websocket.js#L15

One line in the websocket.js file still uses a hardcoded server location; localhost. This gave some problems when running the servers on separate machines. I think it is nice to allow one to set this URL from an environment variable. Now, when reading a url from the environment variable, typically it is lead by http://. This needs to be replaced by ws://.

I'll update this in a PR. :wink:

[aaron5670]

I look forward on your PR. 😃