Refactor sort using operator overloading

[tmancey]

Recommended to refactor the following code (not just limited to PublisherInfo):

bool PublisherInfo::operator<(const PublisherInfo& rhs) const {
    return score > rhs.score;

to

bool PublisherInfoSort(PublisherInfo const& lhs, PublisherInfo const& rhs) {
    return lhs.score > rhs.score;
}

std::sort(publisher_info.begin(), publisher_info.end(), &PublisherInfoSort);