Add C++ nested class example

This also reverts the nested class additions to the Java/C# 'class' example
so that the 'class' example remains identical across different language modules

Examples/java/nested/example.cxx

@@ -0,0 +1,62 @@
+#include "example.h"
+
+int MotorCar::DesignOpinion::AceDesignCount = 0;
+int MotorCar::DesignOpinion::TotalDesignCount = 0;
+
+int MotorCar::DesignOpinion::PercentScore() {
+  return AceDesignCount*100/TotalDesignCount;
+}
+
+MotorCar::Wheels::Wheels(Shape shape, size_t count) : shape(shape), count(count) {}
+
+MotorCar::WindScreen::WindScreen(bool opaque) : opaque(opaque) {}
+
+MotorCar::MotorCar(const std::string &name, const Wheels &wheels, const WindScreen &windscreen) : name(name), wheels(wheels), windscreen(windscreen) {}
+
+MotorCar MotorCar::DesignFromComponents(const std::string &name, const Wheels &wheels, const WindScreen &windscreen) {
+  MotorCar car = MotorCar(name, wheels, windscreen);
+  DesignOpinion::TotalDesignCount++;
+  if (car.wheels.Opinion().itrocks && car.windscreen.Opinion().itrocks)
+    DesignOpinion::AceDesignCount++;
+  return car;
+}
+
+MotorCar::DesignOpinion MotorCar::Wheels::Opinion() {
+  DesignOpinion opinion;
+  opinion.itrocks = true;
+  if (shape == Square) {
+    opinion.itrocks = false;
+    opinion.reason = "you'll have a few issues with wheel rotation";
+  }
+  if (count <= 2) {
+    opinion.reason += opinion.itrocks ? "" : " and ";
+    opinion.itrocks = false;
+    opinion.reason += "a few more wheels are needed for stability";
+  }
+  if (opinion.itrocks)
+    opinion.reason = "your choice of wheels was top notch";
+
+  return opinion;
+}
+
+MotorCar::DesignOpinion MotorCar::WindScreen::Opinion() {
+  DesignOpinion opinion;
+  opinion.itrocks = !opaque;
+  opinion.reason = opinion.itrocks ? "the driver will have a commanding view out the window" : "you can't see out the windscreen";
+  return opinion;
+}
+
+std::string MotorCar::WillItWork() {
+  DesignOpinion wh = wheels.Opinion();
+  DesignOpinion ws = windscreen.Opinion();
+  std::string willit;
+  if (wh.itrocks && ws.itrocks) {
+    willit = "Great car design because " + wh.reason + " and " + ws.reason;
+  } else {
+    willit = "You need a rethink because ";
+    willit += wh.itrocks ? "" : wh.reason;
+    willit += (!wh.itrocks && !ws.itrocks) ? " and " : "";
+    willit += ws.itrocks ? "" : ws.reason;
+  }
+  return willit;
+}