Switch debugoverlay functions to better optional argument checking
* Potential breakage point: If given invalid type for optional argument, no longer do nothing but throw an error, but should be a tiny bit faster now
Added Player:SetFlashlightColor (clientside only, but works on others)
Minor cleanup: Remove GetPlayerEntIndex from headers
Fixed Player:Flashlight playing sounds when nothing changes
Use `gmod_flashlight` attachment for flashlight if it exists
This works for player models, world models and view models
Spawnicon resize menu: work around the weird offset with icons
Added ability to select what weapon Creator Tool spawns NPCs with