Tests: hard-code minitest < 5.0.0 until 5.0.0 compatibility issues can be looked at in detail
FGCP: read FGCP_CERT_DIR env var in method instead of start of class
to allow unit tests to set it.
The old way stopped working because drivers are now preloaded at startup.
Tests: skip tests on Windows that rely on fork() as it is not supported
Tests: fix minor typos in readme.
Tests: add 'network_interfaces' to expected attributes in instances
Tests: correct number of instances owned by 'mockuser'
(inst3's owner is mockuser base64 encoded)