Nanoservice

* Add pickle encoder
* Add timeouts to tests

* Subscriber bug fix

This release includes heavy refactoring

* Renamed Classes: `Client` becomes `Requester`, and `Service` becomes `Responder`. Although old classes are still accessible, when instantiated they will emit warnings.
* Added a new abstract class Endpoint
* Rewrote process method of Subscriber
* Any endpoint (Requester, Publisher, etc) can now be `binded` OR `connected` to a nanomsg address; simply supply the boolean flag `bind` when instantiated.
* Add support for timeouts. When instantiating an endpoint, just supply a pair `timeouts=(10, 10)` which represents (sendTimeout, recvTimeout) AS MILLISECONDS

* Part of service module were rewritten, so that it does not explode when failing to decode a request
* Better testing

* Improve authenticator performance

* Rename Service and Client `recv` method to `receive`
* Add crypto module
* Add optional message authentication between endpoints
* PubSub logic moved to a new module
* PubClient renamed to Publisher
* SubService renamed to Subscriber