Enhanced functionality for conditional impacts

[Kestrellius]

This PR adds a suite of new options to the conditional impacts system, including:

• support for subsystem armor as a condition
• special cases for asteroids, debris, and empty space
• a system to detect cases where a long laser is overpenetrating its impact point, and spawn an additional effect at the laser's head to help conceal the overpenetration
• options for conditioning an effect on the ratio between damage dealt and hitpoints left
• a few other boolean options for controlling when effects can or can't play

This required a certain amount of moving things around, but I'm pretty sure I got all the code paths and behavior will not be changed given the same tables.