message: Remove non existent configuration parameters from May '18 activation test
  may152018activationtime and replayprotectionactivationtime seem to be
  valid ABC parameters, though. Guess that this was a left over from some
  backports we did in preparation for the May '18 upgrade.
diff: @@ -35,9 +35,7 @@ class May152018ActivationTest(ComparisonTestFramework):
  def set_test_params(self):
  self.setup_clean_chain = True
  - self.extra_args = [['-whitelist=127.0.0.1',
  - "-may152018activationtime=%d" % MAY152018_START_TIME,
  - "-replayprotectionactivationtime=%d" % (2 * MAY152018_START_TIME)]]
  + self.extra_args = [['-whitelist=127.0.0.1']]
  def create_and_tx(self, count):
  node = self.nodes[0]
  