In preparation for the potential Taproot soft fork, libconsensus should be updated to support verifying Taproot scripts.

There are two changes I see as necessary:

- Add a VERIFY_TAPROOT flag
- Change the API to support passing in spent outputs (bitcoinconsensus_verify_script_with_spent_outputs?)
{
        assert(havePush);
        std::vector<unsigned char> datain = ParseHex(hexin);
        std::vector<unsigned char> dataout = ParseHex(hexout);
        assert(pos + datain.size() <= push.size());
        BOOST_CHECK_MESSAGE(std::vector<unsigned char>(push.begin() + pos, push.begin() + pos + datain.size()) == datain, comment);
        push.erase(push.begin() + pos, push.begin() + pos + datain.size());
        push.insert(push.begin() + pos, dataout.begin(), dataout.end());
        return *this;
    }
    TestBuilder& DamagePush(unsigned int pos)
    {
        assert(havePush);
        assert(pos < push.size());
        push[pos] ^= 1;
        return *this;
    }
    TestBuilder& Test()
    {
        TestBuilder copy = *this; 
        DoPush();
        DoTest(creditTx->vout[0].scriptPubKey, spendTx.vin[0].scriptSig, scriptWitness, flags, comment, scriptError, nValue);
        *this = copy;
        return *this;
    }
    TestBuilder& AsWit()