Huge refactor of how skills work. A skill is now a collection of SkillAttributes, that each represent one property (radius, cooldown, damage, cost, etc.). This will allow for rather easy addition of new skills and usage of some specific characteristics after initial level randomization.

The genetic algo for now picks 3 attributes among all. This is obviously not ideal, as it doesn't take into account whether the attributes are positive or negative ones. Meaning that having more attributes could mean more malus.
Additional fixes on Skill generation