Sampling Memory Allocations

• StartSampling and StopSampling just wrap the respective v8 API calls

NAN_METHOD(StartSampling) {
  Local<Integer> interval = info[0].As<Integer>();
  Local<Integer> stack_depth = info[1].As<Integer>();
  HeapProfiler* hp = info.GetIsolate()->GetHeapProfiler();
  hp->StartSamplingHeapProfiler(interval->Value(), stack_depth->Value());
}

NAN_METHOD(StopSampling) {
  HeapProfiler* hp = info.GetIsolate()->GetHeapProfiler();
  hp->StopSamplingHeapProfiler();
}

exports->Set(Nan::New<String>("startSampling").ToLocalChecked(),
    Nan::New<FunctionTemplate>(StartSampling)->GetFunction());
  exports->Set(Nan::New<String>("stopSampling").ToLocalChecked(),
    Nan::New<FunctionTemplate>(StopSampling)->GetFunction());