Add a convenience 'expectedFailureNetBSD' decorator and mark all tests
currently failing on NetBSD with it. Also skip a few tests that hang
the test suite. This should establish a baseline for the test suite
and get us closer to enabling tests on buildbot. This will help us
catch regressions while we still have a lot of work to do to get tests
It seems that there are also some flaky tests. I am going to address
them later on.