Initial particle lights config system

[doodlum]

This uses a config system with defaults, to control different basic settings about particle lights.

Typically, all that is needed is to control the culling parameter which should always be enabled on any particle light textures that are empty, but this method also avoids false positives such as on the player torch or candlelight spell, as well as scenarios, mainly with Rudy ENB Lights where the radius is much larger than the actual light to avoid frustum culling issues.

The flicker parameters are based on the game's own system, but implement completely differently.

The config loader class was separated due to how large LightLimitFix.cpp file is becoming, as well as it existing outside of rendering.