Organize the engine/ directory, take 3

Renamed `title` to `movies`.
Moved some functions from `engine/routines/` to their fitting
directories, and cleaned up the base `engine/` directory.
Moved `engine/pokemon/tmhm.asm` back to `engine/items/`.

Made a new subdirectory:
* engine/tilesets: Contains all map-related graphics routines.

engine/tilesets/map_palettes.asm

@@ -0,0 +1,86 @@
+SwapTextboxPalettes:: ; 4c000
+	hlcoord 0, 0
+	decoord 0, 0, wAttrMap
+	ld b, SCREEN_HEIGHT
+.loop
+	push bc
+	ld c, SCREEN_WIDTH
+.innerloop
+	ld a, [hl]
+	push hl
+	srl a
+	jr c, .UpperNybble
+	ld hl, wTilesetPalettes
+	add [hl]
+	ld l, a
+	ld a, [wTilesetPalettes + 1]
+	adc 0
+	ld h, a
+	ld a, [hl]
+	and $f
+	jr .next
+
+.UpperNybble:
+	ld hl, wTilesetPalettes
+	add [hl]
+	ld l, a
+	ld a, [wTilesetPalettes + 1]
+	adc 0
+	ld h, a
+	ld a, [hl]
+	swap a
+	and $f
+
+.next
+	pop hl
+	ld [de], a
+	res 7, [hl]
+	inc hl
+	inc de
+	dec c
+	jr nz, .innerloop
+	pop bc
+	dec b
+	jr nz, .loop
+	ret
+
+ScrollBGMapPalettes:: ; 4c03f
+	ld hl, wBGMapBuffer
+	ld de, wBGMapPalBuffer
+.loop
+	ld a, [hl]
+	push hl
+	srl a
+	jr c, .UpperNybble
+
+; .LowerNybble
+	ld hl, wTilesetPalettes
+	add [hl]
+	ld l, a
+	ld a, [wTilesetPalettes + 1]
+	adc 0
+	ld h, a
+	ld a, [hl]
+	and $f
+	jr .next
+
+.UpperNybble:
+	ld hl, wTilesetPalettes
+	add [hl]
+	ld l, a
+	ld a, [wTilesetPalettes + 1]
+	adc 0
+	ld h, a
+	ld a, [hl]
+	swap a
+	and $f
+
+.next
+	pop hl
+	ld [de], a
+	res 7, [hl]
+	inc hl
+	inc de
+	dec c
+	jr nz, .loop
+	ret