Add simple micro benchmark & testing macro
Cleanup "AISDI.cpp" (tests shouldn't be here)
Application structure cleanup - use as much of MVC as possible
[Tests] Add Containers tests - part 1 - Email class
[Tests] Add Containers tests - part 2 - Attachment class
[Tests] Add Containers tests - part 3 - Person class
[Tests] Add Containers tests - part 4 - Mail class
Pointers to sender & receiver should be const (pointers, not objects!)
[Tests] Show number of tests failed & tell the user if all tests has passed or not