CI

run tests after all env.Install calls #238

# to view logs

Run time

Learn about OS # on GitHub Actions

Job	Run time
win-scons	7m 18s
macos-xcode	6m 42s
linux	7m 52s
macos-scons	7m 14s
win-vs32	13m 58s
win-vs64	14m 17s
	57m 21s