Kue has a different options configuration than redis.createClient

Use case - I would like to use a redis configuration with both a URL and options, like
```js
const kueOptions = {
redis: { url: 'my-connection-url', tls: { servername: 'my-servername' } }
}
```

I've provided a PR and a more detailed description
https://github.com/Automattic/kue/pull/1178

Start by reading the configuration example in this issue and the linked pull request #1178, which contains the detailed description. Trace how Kue passes Redis configuration to redis.createClient; the work is done when a Redis URL can be used together with options such as tls.servername.

Written by the indexing model from the issue text.