Update Twitch API

[hayesmaker]

Isn't Twitch deprecating Kraken, shouldn't this be using the new Twitch api?

[ickybodclay]

@hayesmaker According to migration document, you can still use kraken endpoint, you just have to explicitly specific v5: https://dev.twitch.tv/docs/v5#requests

I don't think this repo has anyone looking after it unfortunately, but If you check my PR #4, I've fixed this issue.

Update: it looks like v5 is now deprecated as well, I will look to update to use "Get Users" helix endpoint.