1. Download ch13_tdd_v2.h/.cpp and perform next phase refactoring. In this phase, we will add a copy constructor, assignment operator, and element-wise operation operators such as +, -, *, /, and...

1. Download ch13_tdd_v2.h/.cpp and perform next phase refactoring. In this phase, we will add a copy constructor, assignment operator, and element-wise operation operators such as +, -, *, /, and more. More specifically, we need to do the following things:

(a) Add the third test case to our test suite, that is, ch13_tdd_Boost_UTF2.cpp.

(b) Add the implementations of these functions to files; for example, ch13_tdd_v2.h/.cpp.

(c) Run the test suite to test them.