Overhaul turning off Visual Effects on low Frames per Sec

When the game detects a low fps count using DetailMinFrameRateNormal and DetailBufferZoneWidth, certain visual effects are turned off. The sum of their defaults is 20. This means if a game speed with 20 or fewer frames per second is chosen, detail will always be turned off.

Change this so the game speed is factored in and if the fps are less than 20 deliberately, do not turn off the visual effects.

This affects spotlights from Combat Lights not drawing at all, Lasers drawing as lines instead of as fancy lasers, and non-damaging particles and certain animations not being displayed.