Add 0 entry to vTxSigOps when adding quorum commitments (#2489)
Add 0 entry to vTxSigOps when adding quorum commitments (#2489)

This fixes a crash observed on Travis. The same crash is likely to happen
outside of Travis as well later.
ivansib/sibcoin,ivansib/sibcoin,ivansib/sibcoin,ivansib/sibcoin,ivansib/sibcoin,ivansib/sibcoin