cyb_95 integrate auth to ruby client

There should be a set_auth_client method on the StreamClient object as well (which might simply delegate to this), since the user should only be interacting with the streamclient, and not care about the rest object.

```ruby
client = StreamClient.new
client.set_auth_client ...
```
instead of
```ruby

client = StreamClient.new
client.rest.set_auth_client ...
```

(Try to make the interfaces as similar to java as possible).