message: force panic in Add operator
diff: @@ -324,7 +324,7 @@ impl ops::Add<Uint128> for Uint128 {
  type Output = Self;
  fn add(self, rhs: Self) -> Self {
  - Uint128(self.u128() + rhs.u128())
  + Uint128(self.u128().checked_add(rhs.u128()).unwrap())
  }
  }
  @@ -332,19 +332,19 @@ impl<'a> ops::Add<&'a Uint128> for Uint128 {
  type Output = Self;
  fn add(self, rhs: &'a Uint128) -> Self {
  - Uint128(self.u128() + rhs.u128())
  + Uint128(self.u128().checked_add(rhs.u128()).unwrap())
  }
  }
  impl ops::AddAssign<Uint128> for Uint128 {
  fn add_assign(&mut self, rhs: Uint128) {
  - self.0 += rhs.u128();
  + self.0 = self.0.checked_add(rhs.u128()).unwrap();
  }
  }
  impl<'a> ops::AddAssign<&'a Uint128> for Uint128 {
  fn add_assign(&mut self, rhs: &'a Uint128) {
  - self.0 += rhs.u128();
  + self.0 = self.0.checked_add(rhs.u128()).unwrap();
  }
  }
  