Trader NPC & Lake of Rage "Town"

This adds the Trader NPC to the Lake of Rage and restores its "town" environment.

The town is themed around evolution. The mart sells all the "normal" evolution stones, aiming to solve Johto's "stone problem" for Pokemon like Vulpix and Bellsprout. The Trader NPC actualises this, being at a point where most Pokemon are around Level 35-40, as is how we balanced it on Cinnabar Island in KEP.

The text is mostly revolved around the Gyarados, but this could shift.

The Gym isn't done - I don't have time to sort it at the moment - but I am thinking of making it a Pre-Gym. This doesn't make a lot of sense though, so maybe it should be changed to be the tower seen in an earlier build.

data/items/marts.asm

@@ -35,6 +35,7 @@ Marts:
 	dw MartMtMoon
 	dw MartIndigoPlateau
 	dw MartUnderground
+	dw MartLakeOfRage
 	assert_table_length NUM_MARTS
 
 MartCherrygrove:
@@ -405,3 +406,18 @@ DefaultMart:
 	db POKE_BALL
 	db POTION
 	db -1 ; end
+
+; Excludes the Moon and Sun Stones, which are "treasure" items.
+; Designed to solve the "stone problem" faced by Pokemon like Bellsprout in the early-game.
+MartLakeOfRage:
+	db 9
+	db FIRE_STONE
+	db THUNDERSTONE
+	db WATER_STONE
+	db LEAF_STONE
+	db HEART_STONE
+	db POISON_STONE
+	db ICE_STONE
+	db DUSK_STONE
+	db SHINY_STONE
+	db -1 ; end