Unit Tests for PagedQuery

I've just checked-in some Gaeunit unit tests for PagedQuery. I have also included the gaeunit.py script and a simple app.yaml file.

To run the unit tests, checkout the trunk (if you have not already) and launch the development server pointing at the source folder. Then navigate to the local /test folder in your browser (probably http://localhost:8080/test), which will run all of the tests defined by the library (19 so far).