Add some more unit tests.

Streamline the unit test test routine.
Slight rework of test function to reduce the amount of text a bit.
Modify the test function to remember the previous test and line number so each is only counted once even though there could be multiple conditions asserted in each test.
Respacing code
Put back a lost test
Remove the temporary function that returns the test and results closures.
Make the test function argument if the condition passes not fails to improve code comprehension.
Update the setErrHandler call to return the previous error handler.