DNF 3: better performance and a move to C++

Templates will generate code specialized for different types which can speed things up immensely. Try sorting a list of doubles with std::sort and qsort. The latter will be slower.

There's also a more subtle reason: C++ allows you to abstract over things that C doesn't, hence allowing better code re-use. And you're more likely to use good algorithms and data structures if somebody else built them generically and put them into an easy-to-use library than if you have to build them yourself.