Fix issue # 8 where exceptions thrown within the callback are swallowed up, causing test cases to seemingly pass even though it fails

Fix issue #8 where exceptions thrown within the callback are swallowed up, causing test cases to seemingly pass even though it fails
(AssertionError exception not being thrown back to the test framework).

Still verifying whether this fix addresses the issue full; sorting out test cases that failed. A lot of test cases are failing. So far they are due to incorrect test cases.


See issue #8 for more discussion