ReplSetConfig::operator== may incorrectly return true if two instances differ only in the value of buildIndexes.

buildIndex == r.buildIndexes

buildIndexes == buildIndexes

                return _id==r._id && votes == r.votes && h == r.h && priority == r.priority &&

                       arbiterOnly == r.arbiterOnly && slaveDelay == r.slaveDelay && hidden == r.hidden &&

                       buildIndexes == buildIndexes;