Add bunch of docstring and some tests

pyAmakCore/classes/agent.py

pyAmakCore/classes/amas.py

pyAmakCore/tests/test_agent/__init__.py

pyAmakCore/tests/test_agent/test_amas.py

pyAmakCore/tests/test_agent/test_class_id.py

pyAmakCore/tests/test_agent/test_environment.py

pyAmakCore/tests/test_agent/test_neighbour.py

pyAmakCore/tests/test_amas/test_agent.py

pyAmakCore/tests/test_amas/test_nbr_cycle.py