Changing the size back to integers.

- Well, with a name that references one.
Include explicit results.

- Damage/shot taken is now tracked.
Include some more tests for demonstration.
Merge branch 'named_results' into weapon_size
Implement damage calculation method

- This is based on weapon size against ship size.  Smaller the ship vs.
  the weapon against it, the less damage it takes if below a certain
  threshold.
Testing battle with different sizes.