Added source file, samples and Makefile.
Update Makefile
changes
Merge branch 'lab3' of https://github.com/ZhbanovaAnna/devtools-course into lab3

Conflicts:
	code/anna-zhbanova/Makefile
	code/anna-zhbanova/docs/Triangle.rst
	code/anna-zhbanova/include/Triangle.hpp
	code/anna-zhbanova/samples/Triangle_sample.cpp
	code/anna-zhbanova/src/Triangle.cpp
changes
Merge pull request #45 from ZhbanovaAnna/lab3

[KK] Жбанова - лабораторная работа #3