Windows testing

[Byron]

Previously, it was 3 errors and 3 failures, it shouldn't be more now.

[Byron]

Most of the regression comes from the massive amount of submodule tests, and from file-access issues in test_doc.

Overall I believe it's not worse than before, even though I believe there could be issues with submodules.
As windows-work is something I'd gladly avoid, I will wait for issues to be posted here before digging in deeper.