Bugs fixed, added parameters to TreeEngine.

Fixed possible infinite recursion problems, when there are cycles in
best variant.
Added parameters to TreeEngine to improve best variant depth and
stability.
Added DynamicsEvaluator with more complex position valoration.

(Still very basic)
Use DynamicsEvaluator instead of SimpleEvaluator in tests
Use DynamicsEvaluator instead of SimpleEvaluator. Stop properly when
game ends.