fix: damage reputation loss is now proportional rather than constant

[BenjaminAmos]

Description

This pull request changes reputation loss due to damage to be proportional to the damage inflicted, rather than constant per-hit. It also changes the damage handling code to take into account the instigator of the damage, removing a previous constraint where the projectile code directly managed reputation loss, which was a poor place to handle this in.

It also implements a fixed penalty reputation loss when a ship is destroyed, which was previously referenced in the code but unimplemented.

Testing

• Start a new game with the Loaded Imperial Large ship
• Fire on the starting station until it starts firing back.
• Destroy a few of the guards
• Fly around and verify that other Imperial faction ships are now hostile to you

Notes

This fixes #729.