Check possibility for opinionated consumer wrappers

[nick-zh]

In a discussion with the maintainer of librdkafka, he proposed to have:

I'm very much in favour of high-level opinionated wrappers. Most (new) Kafka users don't really know what to do with all the bells and whistles, and they're much better off with a simpler this-is-one-way-to-do-it solution.

I totally agree with this, while we already try to do this in our library, maybe there is a way to further improve this, so the "default" behaviour is easier to use / we give users a quicker way to jump in and use a consumer / producer.

Also add documentation for this.