o Minor bugfixes (testing):
    - Skip test_rebind when the TOR_SKIP_TEST_REBIND environmental variable is
      set. Fixes bug 30713; bugfix on 0.3.5.1-alpha.
    - Skip test_rebind on macOS in Travis, because it is unreliable on
      macOS on Travis. Fixes bug 30713; bugfix on 0.3.5.1-alpha.