Added a benchmark tool

Source/Problem6.cpp

@@ -35,7 +35,6 @@ int Problem6::START_NUM = 1;
 int Problem6::END_NUM = 100;
 
 Problem6::Problem6() : Problem("Find the difference between the sum of the squares of the first one hundred natural numbers and the square of the sum."), sumOfSquares(0), squareOfSum(0){
-
 }
 
 void Problem6::solve(){
@@ -94,3 +93,8 @@ uint64_t Problem6::getDifference() const{
 	}
 	return abs(sumOfSquares - squareOfSum);
 }
+
+void Problem6::reset(){
+	Problem::reset();
+	sumOfSquares = squareOfSum = 0;
+}