* PubSub protocol support
Added support for :
- XEP-0050 (Command))
- XEP-0060 (PubSub)
- XEP-0004 (Forms)
Fixed the NewClient function by adding parsing of the domain from the JID if no domain is provided in transport config.
Updated xmpp_jukebox example
* Delete useless pubsub errors
* README.md update
Fixed import in echo example
* Typo
* Fixed raw send on client example
* Fixed jukebox example and added a README.md
This makes it possible to use a factory function to create a transport of the right type and not having to repeat the address when calling Transport.Connect()
* Add constants (enumlike) for stanza types
* NewIQ, NewMessage and NewPresence are now initialized with the Attrs struct
* Update examples
* Do not export backoff code. For now, we do not need to expose backoff in the documentation
* Make presence priority an int8
