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/pokemon_league_gate.asm

@@ -1,4 +1,4 @@
-_UnnamedText_1e704: ; 8cfbb (23:4fbb)
+_UnnamedText_1e704:: ; 8cfbb (23:4fbb)
 	text "Only truly skilled"
 	line "trainers are"
 	cont "allowed through."
@@ -6,14 +6,14 @@ _UnnamedText_1e704: ; 8cfbb (23:4fbb)
 	para "You don't have the"
 	line "BOULDERBADGE yet!@@"
 
-_UnnamedText_1e715: ; 8d012 (23:5012)
+_UnnamedText_1e715:: ; 8d012 (23:5012)
 	db $0
 	para "The rules are"
 	line "rules. I can't"
 	cont "let you pass."
 	done
 
-_UnnamedText_1e71a: ; 8d03e (23:503e)
+_UnnamedText_1e71a:: ; 8d03e (23:503e)
 	text "Oh! That is the"
 	line "BOULDERBADGE!"
 	cont "Go right ahead!@@"