Feature: Shield/ Hull For Ships, Facilities and Bases

[Steelstone3]

Depends on #63

• [ ] When a projectile hits a starship or space facility it takes damage
  • [ ] If the shields are above 0 then all incoming damage depletes the shield until it reaches 0 (no bleed through)
  • [ ] If the shields are disabled the hull will take damage
  • [ ] When the hull is 0 the space facility or starship is destroyed