Jedis Pub/Sub doesn't allow to subscribe more than once other than sequentially

[marcosnils]

Current Pub/Sub implementation is blocking and doesn't allow the same connection to subscribe to more than one channel in a nice and friendly way. The only way of achieving it now is by doing some logic in the pubsub listener methods which is not intuitive and straightforward.

Some observations have been discussed here already: https://github.com/xetorthio/jedis/issues/996#issuecomment-104432661. The idea of this issue is to look for better implementations so Jedis Pub/Sub can be something beautiful to use

Suggestions are welcome!