Add support for OBS stream status and stream key update.

[lamaral]

Lange,

I extended the nodecg-utility-obs to obtain information if OBS is streaming and added the option to change the stream key from NodeCG.

I hope the code is useful. If it's not up to the standards, feel free to either direct me on how to enhance or fix as you would like.

[lamaral]

I realized the documentation is missing. I'll take care of it tomorrow.

[lamaral]

859b7b2 contains the requested changes and updated documentation.

Please double check if I changed all space indentation to tabs.

[lamaral]

I've struggled quite a lot trying to get it right, but the lint is asking for a change that breaks the obs-websocket-js library.

The lint complained I should use the shorter settings.key but if I do, the library complains that settings wasn't defined.

If you wanna close this PR, I don't mind.

[Hoishin]

what exactly is the eslint error?

[lamaral]

<path>/nodecg-obs/packages/nodecg-utility-obs/index.js
  162:29  error  Unnecessarily quoted property 'settings' found  quote-props
  162:42  error  Unnecessarily quoted property 'key' found       quote-props
  162:42  error  Expected property shorthand                     object-shorthand

[Hoishin]

Run

npm run pretest -- --fix

And see if the same error happens after that.