This uses the new non-parallel-at-the-end I added to xUnit in https://github.com/xunit/xunit/pull/1411 This way we can run any global test that are other-test-unfriendly much more easily.
OperationsPerInvoke is an informational, not instructional property.
What we actually want is the UnrollFactor. Moved into the job definition
to simplify things.
This is based on BenchmarkDotNet (while preserving the legacy format
with minor improvements as well - legacy runs much faster). See #666 for
details. Not an ominus number at all.
Note: this code will get a bit simpler with BenchmarkDotNet categories,
see https://github.com/dotnet/BenchmarkDotNet/issues/248 for details.
Nick Craver