Version 2.0.0-beta.21 does not contain the streamClient or any voice functionality

[Beslinda]

I am trying to use stream client but it is not available on the ApiAiClient. This is what I am doing

private apiAiStreamClient: IStreamClient;
readonly client = new ApiAiClient({accessToken: 'xxxx',streamClientClass: ApiAiStreamClient})

this.apiAiStreamClient = this.client.createStreamClient(); // this client does not contain a function createStreamClient. Even when I check in the node modules it seems like the voice part is not there are all .

Which version of this modules should I use ? Where to find documentation about this issue.