Detach SKActor from the Evolvable dependency
Renamed AbstractSystem into ParticleSystem and
improved giving it a non-template identity
Taking it as a template class was too dangerous, then
the list containing components changed to std::list<Particle*> type
Scene contains an Evolvable list separate from the SKActor list
OscillatorShape renamed into OscillatorParticle
NewtonParticle class created
NewtonParticle and OscillatorParticle are children of Particle