v0.7.0

• An environmental skip (markTestSkipped(), markTestIncomplete()) is
  reported to the engine as TrialOutcome::skipped() rather than as a plain
  discard, so a recorded regression whose replay only skipped is kept instead
  of pruned. A machine without the dependency the body guards against used to
  delete the counterexample for every machine that has it. Requires
  rasuvaeff/property-testing-core ^0.8.