Increase minimum level for merchant tunnels event to 18

Having such a low minimum level isn't accomplishing anything besides killing new players and annoying experienced ones who have to avoid areas it can spawn

game/modules/tome/data/general/encounters/maj-eyal.lua

@@ -44,9 +44,9 @@ newEntity{
 newEntity{
 	name = "Lost merchant",
 	type = "hostile", subtype = "special", unique = true,
-	level_range = {10, 20},
+	level_range = {14, 28},
 	rarity = 7,
-	min_level = 10,
+	min_level = 18,
 	on_world_encounter = "merchant-quest",
 	on_encounter = function(self, who)
 		who.energy.value = game.energy_to_act

game/modules/tome/data/zones/thieves-tunnels/zone.lua

@@ -19,14 +19,14 @@
 
 return {
 	name = "Unknown tunnels",
-	level_range = {8, 18},
+	level_range = {14, 28},
 	level_scheme = "player",
 	max_level = 2,
 	actor_adjust_level = function(zone, level, e) return zone.base_level + e:getRankLevelAdjust() + level.level-1 + rng.range(-1,2) end,
 	width = 30, height = 30,
 	ambient_music = "Zangarang.ogg",
-	min_material_level = 1,
-	max_material_level = 2,
+	min_material_level = 2,
+	max_material_level = 3,
 	generator =  {
 		map = {
 			class = "engine.generator.map.TileSet",