Add Field class

empty class containing only pointer to token, which stands on this field.
Add Attribute class
Add BoardToken class

containing pointer to field on which this token is standing and attributes mapped to names.
Add testGetAttribute

Add TokenTest class, write simple test to check if BoardToken returns attribute correctly, adding new constructor for BoardToken in the process.
Modify appropriate CMakeLists.txt file to create test executable for Token class.
Add enum representing orientation of a token on a game board.
Add testAddAttribute

and change name of the test case to BoardTokenTest
Add test suite for Attribute class

with tests for getters.
Add rotation attribute

and also add method getRotation(), initialize rotation properly in constructor.
Add testGetRotation.
Enable upgrading attribute's value

and add ability to rotate board tokens.
REVIEW
after REVIEW 31e9943
Added missing destructor, missing base constructor call, removed unused constructor, added parameters to constructors and some other cleaning
Merge remote-tracking branch 'origin/feature/BoardTokenClass' into develop