Pypubsub

- Import/export of topic tree and its documentation using Python interpreter
- Better support for evolving topic tree during application development,
with "freezing" certain parts of tree
- Helper functions to transition from *arg1* to *kwargs* messaging protocol
- Improved error messages (in exceptions raised)
- PyPubSub can be installed inside other packages and will not interfere with
system-wide pubsub
- pubsubconf module moved inside pubsub package so manual install easier
- Support !**kwargs in listeners
- Support for more than one pubusb notification handler
- Multiple publisher engines in one application (for instance, in separate
threads, or for different "domains" in a large application)
- Upgraded docs
- Bug fixes, cleanup

- Use keyword arguments in sendMessage
- Support any kind of listener, not just those with one unnamed argument
- Validate listeners at subscription time
- Support "inheritance" of keyword arguments by subtopics during
message sending (prevents a common bug which was to send data using
wrong argument names).
- Topic tree can be documented (including topic message arguments)
- Support user-defined notification handling of certain events occuring in
PyPubSub such as "subscribe", "sendMessage".
- Support user-defined exception handling of exceptions raised by
listeners
- Proto-Documentation on own website using Sphinx
- Separate regression testing folder for nose-based automated testing
- Configuration module for choosing which PyPubSub API to use in application,
useful for backwards compatibility

- more Pythonic API (new ``PublisherClass`` API, at module level
so easier to call -- no need to know about singleton)
- Support definition of topic tree via a python class, for increased
rigor and documentability of topics
- Topics are objects

- Created by Rob Shecter in wxPython's ``wx.lib`` (early 2000?)
- Weakmethod added by Oliver Schoenborn (2004)
- Further development transfered to Schoenborn (2004)