delete a bit of useless vars (#589)

code/game/objects/items/explosives/grenades/grenade.dm

@@ -25,10 +25,6 @@
 	var/arm_sound = 'sound/weapons/grenade/grenade_pinout.ogg'
 	var/hud_state = "grenade_he"
 	var/hud_state_empty = "grenade_empty"
-	///Light impact range when exploding
-	var/light_impact_range = 4
-	///Weak impact range when exploding
-	var/weak_impact_range = 0
 	var/G_throw_sound = 'sound/weapons/grenade/grenade_throw.ogg'
 	/// Power of the explosion
 	var/power = 105

code/game/objects/items/explosives/grenades/marines.dm

@@ -24,7 +24,6 @@
 	item_state = "grenade_pmc"
 	hud_state = "grenade_frag"
 	icon_state_mini = "grenade_red_white"
-	light_impact_range = 5
 	power = 125
 	falloff = 40
 
@@ -39,7 +38,6 @@
 	item_state = "grenade_ex"
 	hud_state = "grenade_frag"
 	icon_state_mini = "grenade_yellow"
-	light_impact_range = 5
 	power = 125
 	falloff = 40
 
@@ -78,7 +76,6 @@
 	icon_state = "alien_grenade"
 	item_state = "alien_grenade"
 	hud_state = "grenade_frag"
-	light_impact_range = 6
 	power = 150
 	falloff = 25
 	overlay_type = "yellow"
@@ -89,8 +86,6 @@
 	icon_state = "grenade_sticky"
 	item_state = "grenade_sticky"
 	det_time = 5 SECONDS
-	light_impact_range = 2
-	weak_impact_range = 3
 	icon_state_mini = "grenade_sticky"
 	arm_sound = 'sound/weapons/grenade/grenade_pinout4.ogg'
 	power = 90
@@ -216,7 +211,6 @@
 	icon_state = "grenade_sticky_cloak"
 	item_state = "grenade_sticky_cloak"
 	det_time = 5 SECONDS
-	light_impact_range = 1
 	self_sticky = TRUE
 	overlay_type = "green"
 	/// smoke type created when the grenade is primed
@@ -319,8 +313,6 @@
 	icon_state = "ags_grenade"
 	item_state = "ags_grenade"
 	det_time = 2 SECONDS
-	light_impact_range = 2
-	weak_impact_range = 4
 	power = 80
 	falloff = 20
 	overlay_type = "yellow"
@@ -487,7 +479,6 @@
 	det_time = 4 SECONDS
 	dangerous = TRUE
 	icon_state_mini = "grenade_blue_white"
-	light_impact_range = 3
 	power = 80
 	falloff = 30
 	overlay_type = "blue"