TODO

1. 05/21/2018
  Remove py::nodelete in binding to class where it is unnecessory, such as
  KIM_DataType.hpp.                                                             Done

2. 05/21/2018
  Add py::scoped_interpreter guard{}; to embed functions.                       Done
  Answer: cannot use it. Runtime error will occur.

3. 05/22/2018
  Check whether polymophism works for functions like `set_argument_pointer`
  in KIM_ComputeArguments.hpp.                                                  Done
  Answer: yes, it works.

4. 06/21/2018
  The followting two member functions in KIM_ComputeArguments.hpp and
  KIM_Model.hpp are not wrapper.
    void SetSimulatorBufferPointer(void * const ptr);
    void GetSimulatorBufferPointer(void ** const ptr) const;
  To do it, we can require `ptr` to be a dictionary, and use the same method
  for callbacks to wrap it.  But check with Ryan to see whether this is
  really needed.                                                                Not yet