message: Relax Kak numerical tolerance setting
  Also, add a test case for edge case of numerical tolerance.
diff: @@ -18,6 +18,20 @@ Eigen::Matrix4cd generateRandomUnitary()
  }
  }
  +TEST(KakTester, checkEdgeCase)
  +{
  + Eigen::Matrix4cd unitaryMat;
  + unitaryMat << 1, 0, 0, 0,
  + 0, 2.67948963e-08, -1, 0,
  + 0, 1, 2.67948965e-08, 0,
  + 0, 0, 0, 1;
  + auto tmp = xacc::getService<Instruction>("kak");
  + auto kak = std::dynamic_pointer_cast<quantum::Circuit>(tmp);
  + const bool expandOk = kak->expand({std::make_pair("unitary", unitaryMat)});
  + std::cout << kak->toString() << "\n";
  + EXPECT_TRUE(expandOk);
  +}
  +
  TEST(KakTester, checkSimple)
  {
  const int nbTests = 1000;
  