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/mansion_2f.asm

@@ -1,21 +1,21 @@
-_Mansion2BattleText1: ; 852b7 (21:52b7)
+_Mansion2BattleText1:: ; 852b7 (21:52b7)
 	text "I can't get out!"
 	line "This old place is"
 	cont "one big puzzle!"
 	done
 
-_Mansion2EndBattleText1: ; 852ea (21:52ea)
+_Mansion2EndBattleText1:: ; 852ea (21:52ea)
 	text "Oh no!"
 	line "My bag of loot!"
 	prompt
 
-_Mansion2AfterBattleText1: ; 85302 (21:5302)
+_Mansion2AfterBattleText1:: ; 85302 (21:5302)
 	text "Switches open and"
 	line "close alternating"
 	cont "sets of doors!"
 	done
 
-_Mansion2Text3: ; 85336 (21:5336)
+_Mansion2Text3:: ; 85336 (21:5336)
 	text "Diary: July 5"
 	line "Guyana,"
 	cont "South America"
@@ -25,24 +25,24 @@ _Mansion2Text3: ; 85336 (21:5336)
 	cont "in the jungle."
 	done
 
-_Mansion2Text4: ; 85389 (21:5389)
+_Mansion2Text4:: ; 85389 (21:5389)
 	text "Diary: July 10"
 	line "We christened the"
 	cont "newly discovered"
 	cont "#MON, MEW."
 	done
 
-_UnnamedText_520c2: ; 853c7 (21:53c7)
+_UnnamedText_520c2:: ; 853c7 (21:53c7)
 	text "A secret switch!"
 
 	para "Press it?"
 	done
 
-_UnnamedText_520c7: ; 853e3 (21:53e3)
+_UnnamedText_520c7:: ; 853e3 (21:53e3)
 	text "Who wouldn't?"
 	prompt
 
-_UnnamedText_520cc: ; 853f1 (21:53f1)
+_UnnamedText_520cc:: ; 853f1 (21:53f1)
 	text "Not quite yet!"
 	done