message: implement ospRelease for MPIDistributedDevice
diff: @@ -428,8 +428,9 @@ namespace ospray {
  void MPIDistributedDevice::release(OSPObject _obj)
  {
  - UNUSED(_obj);
  - postStatusMsg(1) << "WARNING: release() not implemented, memory leak!";
  + if (!_obj) return;
  + auto &obj = objectFromAPIHandle<ManagedObject>(_obj);
  + obj.refDec();
  }
  void MPIDistributedDevice::setMaterial(OSPGeometry _geometry,
  