message: Don't use bignum in stake check.
diff: @@ -24,12 +24,14 @@ using namespace std;
  bool stakeTargetHit(arith_uint256 hashProofOfStake, int64_t nValueIn, arith_uint256 bnTargetPerCoinDay)
  {
  //get the stake weight - weight is equal to coin amount
  - arith_uint256 bnCoinDayWeight = arith_uint256(nValueIn);
  - CBigNum bnTarget(bnCoinDayWeight);
  - bnTarget = bnTarget * CBigNum(bnTargetPerCoinDay);
  + arith_uint256 bnTarget = arith_uint256(nValueIn) * bnTargetPerCoinDay;
  +
  + //Double check for overflow, give max value if overflow
  + if (bnTargetPerCoinDay > bnTarget)
  + bnTarget = ~arith_uint256();
  // Now check if proof-of-stake hash meets target protocol
  - return hashProofOfStake < bnTarget.getarith_uint256();
  + return hashProofOfStake < bnTarget;
  }
  bool CheckStake(const CDataStream& ssUniqueID, CAmount nValueIn, const uint64_t nStakeModifier, const uint256& bnTarget,
  