Integrate GTest and add simple tests

[JDRkow]

Integrate GTest and add simple tests.

User story:
As a developer, I want to be sure that project is well tested, so that I can make the feature and fixes without any problem with existing code.

DoD:

• investigate how conan working with unit test
• if its necessary add gtest library to enviroment
• create a separate progect for unit testing
• add a simple test to project

Technical details:

• documentation of gtest