Test coverage for schooltool.traverser

schooltool/      covered 77% (4766 of 21338 uncovered)
    traverser/      covered 96% (7 of 175 uncovered)
        traverser.py      covered 95% (4 of 99 uncovered)
        browser.py      covered 62% (3 of 8 uncovered)
        __init__.py      covered 100% (0 of 1 uncovered)
        interfaces.py      covered 100% (0 of 8 uncovered)
        metaconfigure.py      covered 100% (0 of 31 uncovered)
        metadirectives.py      covered 100% (0 of 28 uncovered)