Make descriptions of insulated wires consistent

This allows finding all of them by searching
"insulated" in the creative menu.

mesecons_extrawires/corner.lua

@@ -49,7 +49,7 @@ minetest.register_node("mesecons_extrawires:corner_on", {
 
 minetest.register_node("mesecons_extrawires:corner_off", {
 	drawtype = "nodebox",
-	description = "Mesecon Corner",
+	description = "Insulated Mesecon Corner",
 	tiles = {
 		"jeija_insulated_wire_curved_tb_off.png",
 		"jeija_insulated_wire_curved_tb_off.png^[transformR270",

mesecons_extrawires/crossover.lua

@@ -19,7 +19,7 @@ local crossover_states = {
 }
 
 minetest.register_node("mesecons_extrawires:crossover_off", {
-	description = "Insulated Crossover",
+	description = "Insulated Mesecon Crossover",
 	drawtype = "mesh",
 	mesh = "mesecons_extrawires_crossover.b3d",
 	tiles = {

mesecons_extrawires/tjunction.lua

@@ -50,7 +50,7 @@ minetest.register_node("mesecons_extrawires:tjunction_on", {
 
 minetest.register_node("mesecons_extrawires:tjunction_off", {
 	drawtype = "nodebox",
-	description = "T-junction",
+	description = "Insulated Mesecon T-junction",
 	tiles = {
 		"jeija_insulated_wire_tjunction_tb_off.png",
 		"jeija_insulated_wire_tjunction_tb_off.png^[transformR180",