Get rid of globals.asm. Use ::s to export labels between objects.

globals.asm was a hack that:
- gave rgbasm an extra 100k lines to read
- increased reliance on the python preprocessor
- made the makefile a mess
- gave object creation an extra step
- wasn't even necessary

This speeds up build time by at least a third.

text/maps/vermilion_house.asm

@@ -1,14 +1,14 @@
-_VermilionHouse1Text1: ; 9c449 (27:4449)
+_VermilionHouse1Text1:: ; 9c449 (27:4449)
 	text "I'm getting my"
 	line "PIDGEY to fly a"
 	cont "letter to SAFFRON"
 	cont "in the north!"
 	done
 
-_VermilionHouse1Text2: ; 9c488 (27:4488)
+_VermilionHouse1Text2:: ; 9c488 (27:4488)
 	text "PIDGEY: Kurukkoo!@@"
 
-_VermilionHouse1Text3: ; 9c49c (27:449c)
+_VermilionHouse1Text3:: ; 9c49c (27:449c)
 	text "Dear PIPPI, I hope"
 	line "to see you soon."