[Gzz] Architectural change

[Tuomas Lukka]

An important architecture change:

        junit -> PyUnit

i.e. all tests from now on will be in jython. The move has already started
but it will be a while until all tests have been moved. Meanwhile, if there
are any problems with a class, please *first* move its unit tests to jython
and then start debugging.

The reason is that jython allows handling of sequences, functional style etc
MUCH easier than Java and the size of the test code will drop and clarity will
increase.

Oh, and as a reminder: we should keep up the policy on fixing bugs:
if a bug is found,

        FIRST make a REPEATABLY FAILING unit test for the bug.

        COMMIT THE TEST TO CVS.

        ONLY THEN fix the bug, and make sure that all junit tests pass.

That way, you can be sure that you fixed the bug and didn't break other things.
And our battery of tests will grow.

        Tuomas