CVAR for disable dynamic light from rpg-rocket, and from explodes

[ynnur]

add cvars like from rofi's dll: (https://user-images.githubusercontent.com/77773919/105319242-c88d9c80-5bee-11eb-9d14-135babd436fe.png)

[SmileyAG]

Implementation you can check here, https://github.com/LevShisterov/BugfixedHL/commit/cd9c832bb86c8f71222c3f0061060e6a101bfb6f

[YaLTeR]

Implementation you can check here, LevShisterov/BugfixedHL@cd9c832

Seems a bit vac-sketchy tbh.

[ynnur]

if tbh, somebody already played without dynamic light, and he doesn't got s'lag ban. and this dynamic light lowers fps greatly.