This recommits D2301, which was reverted due to failures in the windows tests.
This diff fixes those failures by skipping compute log tests when the legacy windows stdio
is not supported (windows python 3.6+, with env var PYTHONLEGACYWINDOWSSTDIO not set.
It also changes some tests that did not handle the difference in windows line separators, and
fixed the tail implementation for windows by swallowing exceptions caused by pytest's stdout