Added a GC interface to cpp

std/cpp/vm/Gc.hx

@@ -0,0 +1,15 @@
+package cpp.vm;
+
+class Gc
+{
+   static public function enable(inEnable:Bool) : Void
+   {
+      untyped __global__.__hxcpp_enable(inEnable);
+   }
+
+   static public function run(major:Bool) : Void
+   {
+      untyped __global__.__hxcpp_collect();
+   }
+
+}