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/celadon_dept_store_4f.asm

@@ -1,10 +1,10 @@
-_CeladonMart4Text2: ; 9cad4 (27:4ad4)
+_CeladonMart4Text2:: ; 9cad4 (27:4ad4)
 	text "I'm getting a"
 	line "# DOLL for my"
 	cont "girl friend!"
 	done
 
-_CeladonMart4Text3: ; 9cafd (27:4afd)
+_CeladonMart4Text3:: ; 9cafd (27:4afd)
 	text "I heard something"
 	line "useful."
 
@@ -14,7 +14,7 @@ _CeladonMart4Text3: ; 9cafd (27:4afd)
 	cont "with a # DOLL!"
 	done
 
-_CeladonMart4Text4: ; 9cb56 (27:4b56)
+_CeladonMart4Text4:: ; 9cb56 (27:4b56)
 	text "Express yourself"
 	line "with gifts!"