Dedicated server compatibility/fixes.

Environment_ForceDisabledDetailProps, various small fixes.

Editor entity bug fixes, additional features, use vanilla flatnormal texture instead of a custom one.

Water Darkening bug fix

Refactoring, QoL, Extra features for static props.

Lua error fix

Fixed lua error caused by GetConvar not always existing when it's called. Fixed players being able to bypass Environment_ForceDisabledSkybox by setting r_3dsky to values other than 1 or 0.

Significantly improved the water darkener, fixed the editor not working correctly, improved various parts of the code/removed broken or un-used things.

Removed the non-vtf version of the spawn menu icon for the editor, which was left in accidentally

Added a texture and icon for the editor, Added something that should make most dynamic lights from other addons work, added a checkbox/convar for setting radiosity to 0, Added a checkbox/convar for making ropes black, Altered the lamp/light fixer code so that it should now almost always work, made some of the code less bad and removed some commented-out code.