Version 2.4
* Created a OpalClient class which wrapps python autogenerated code
* Updated the docs accordingly
* Created a UnitTestOpalClient with UnitTest routines
* updated ApbsClient and the GenericServiceClient with the new OpalClient interface
* _upgraded stubs to the new Opal 2.4 wsdl_

Version 2.2
* Now has a generic Opal client that supports the same functionality as the
  generic Java client
* Updated documentation for the generic Python client

Version 2.0
* Now uses ZSI version 2.1_a2 (patched version of 2.1_a1) to support
  SOAP attachmnts 
* Compatible with the Opal 2.x server-side
* New developer guide for writing Python clients

Version 1.9.3
* Now uses ZSI version 2.1_a1. This eliminates the dependency on PyXML.

Version 1.9.2
* Python clients compatible with opal-care version 1.9.2
