Csvt32745 hand in hw6

[csvt32745]

This PR includes the following files:

1. matrix.hpp : Implementation of the Matrix class
2. bind.cpp : pybind module of matrix.hpp
3. MakeFile : Compile the shared library of Matrix
4. PRELOAD_MKL : Set the condition of ../validate.py

The idea of py::cast came from pybind/pybind11#308 (comment)

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