Remove a silly array wrapper class in factor of std::vector.

Could be refactored more heavily, but then again I'm scared of bounds checking vector implementations...
The choice to not use the vector's size field is for the rest of the code; having a size field in a debug function is fallout for that.

As for not trusting it - actually, here's a question: is `vector::clear()` required by the standard not to deallocate?  [cppreference](http://en.cppreference.com/w/cpp/container/vector/clear) says it is, and it's rarely wrong, but I can't find such language in the C++14 standard, and cplusplus.com merely says it is [not guaranteed to deallocate](http://www.cplusplus.com/reference/vector/vector/clear/).

If it's in the standard that constantly clearing and readding elements is safe, then I will trust it.  Otherwise, I don't know... I'm not terribly familiar with most STL implementations.  If you say that it's safe, I might trust you too :)