Converts some istype's to use helpers (#3224)

Converts various istype's to use helpers. Mainly:
Cable
Wrench
Screwdriver
Multitool
Crowbar
Wirecutter

And makes the helpers defines.

code/modules/modular_computers/NTNet/NTNet_relay.dm

@@ -126,12 +126,12 @@
 	return ..()
 
 /obj/machinery/ntnet_relay/attackby(var/obj/item/weapon/W as obj, var/mob/user as mob)
-	if(istype(W, /obj/item/weapon/screwdriver))
+	if(isscrewdriver(W))
 		playsound(src.loc, 'sound/items/Screwdriver.ogg', 50, 1)
 		panel_open = !panel_open
 		user << "You [panel_open ? "open" : "close"] the maintenance hatch"
 		return
-	if(istype(W, /obj/item/weapon/crowbar))
+	if(iscrowbar(W))
 		if(!panel_open)
 			user << "Open the maintenance panel first."
 			return

code/modules/modular_computers/computers/modular_computer/interaction.dm

@@ -148,7 +148,7 @@
 			try_install_component(user, C)
 		else
 			to_chat(user, "This component is too large for \the [src].")
-	if(istype(W, /obj/item/weapon/wrench))
+	if(iswrench(W))
 		var/list/components = get_all_components()
 		if(components.len)
 			to_chat(user, "Remove all components from \the [src] before disassembling it.")
@@ -162,7 +162,7 @@
 				"You hear a ratchet.")
 			qdel(src)
 		return
-	if(istype(W, /obj/item/weapon/weldingtool))
+	if(iswelder(W))
 		var/obj/item/weapon/weldingtool/WT = W
 		if(!WT.isOn())
 			to_chat(user, "\The [W] is off.")
@@ -179,7 +179,7 @@
 			to_chat(user, "You repair \the [src].")
 		return
 
-	if(istype(W, /obj/item/weapon/screwdriver))
+	if(isscrewdriver(W))
 		var/list/all_components = get_all_components()
 		if(!all_components.len)
 			to_chat(user, "This device doesn't have any components installed.")

code/modules/modular_computers/computers/subtypes/dev_telescreen.dm

@@ -19,7 +19,7 @@
 	is_holographic = TRUE
 
 /obj/item/modular_computer/telescreen/attackby(var/obj/item/weapon/W as obj, var/mob/user as mob)
-	if(istype(W, /obj/item/weapon/crowbar))
+	if(iscrowbar(W))
 		if(anchored)
 			shutdown_computer()
 			anchored = FALSE

code/modules/modular_computers/hardware/ai_slot.dm

@@ -28,7 +28,7 @@
 		stored_card = W
 		W.forceMove(src)
 		update_power_usage()
-	if(istype(W, /obj/item/weapon/screwdriver))
+	if(isscrewdriver(W))
 		user << "You manually remove \the [stored_card] from \the [src]."
 		stored_card.forceMove(get_turf(src))
 		stored_card = null

code/modules/modular_computers/hardware/hardware.dm

@@ -15,7 +15,7 @@
 
 /obj/item/weapon/computer_hardware/attackby(var/obj/item/W as obj, var/mob/living/user as mob)
 	// Multitool. Runs diagnostics
-	if(istype(W, /obj/item/device/multitool))
+	if(ismultitool(W))
 		to_chat(user, "***** DIAGNOSTICS REPORT *****")
 		diagnostics(user)
 		to_chat(user, "******************************")
@@ -31,7 +31,7 @@
 			damage = 0
 		return 1
 	// Cable coil. Works as repair method, but will probably require multiple applications and more cable.
-	if(istype(S, /obj/item/stack/cable_coil))
+	if(iscoil(S))
 		if(!damage)
 			to_chat(user, "\The [src] doesn't seem to require repairs.")
 			return 1