prevent maxDiscardRatio from becoming zero

if max_success > max_discard then maxDiscardRatio
will become zero and quicktest will immediately report
that the test failed because it exhausted all attempts
to generate suitable test data.
Merge branch 'quickcheck-max-discard-error' of git://github.com/cantora/test-framework
Quieten compiler warnings
Bump version to 0.8.0.3
Bump hunit version to 0.3.0.1
Merge branch 'master' of https://github.com/haskell/test-framework