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/events/checktime.asm

@@ -0,0 +1,19 @@
+CheckTime:: ; c000
+	ld a, [wTimeOfDay]
+	ld hl, .TimeOfDayTable
+	ld de, 2
+	call IsInArray
+	inc hl
+	ld c, [hl]
+	ret c
+
+	xor a
+	ld c, a
+	ret
+
+.TimeOfDayTable: ; c012
+	db MORN_F, MORN
+	db DAY_F,  DAY
+	db NITE_F, NITE
+	db NITE_F, NITE
+	db -1