* Created filters to be used with incoming and outgoing message stanzas
* Added a list of ChatMarkersListener and its add and remove methods.
* Added a stanza listener for outgoing messages.
* Added a stanza listener for incoming messages.
* Added discover feature for XEP-0333.
* Added methods to inform a message was: received, displayed or ack
* Added javadoc autor tag.
Miguel Hincapie