This reverts commit 03f7c962.

_resultForDoCleanups no longer exists on python3, getting the status
of a test in teardown is very different accross python versions ( see
https://stackoverflow.com/q/4414234 ) and just executing this code when
the test failed only has the problem that a test method may count as
two failures or errors, which is after all not a big problem.

This TALES is complex, especially if we need to support python3 as well

This reverts commit d4ab7bb5.