Change atari dist disk output to 1050 format, so that GPL can fit.

Author: tschak909

Makefile

@@ -371,7 +371,7 @@ dist-apple2: $(PROGRAM).apple2
 
 dist-atari: $(PROGRAM).atari
 	cp plato.atari dist.atari/files/plato.com
-	dir2atr -b Dos25 720 dist.atari/plato.atr dist.atari/files
+	dir2atr -b Dos25 1040 dist.atari/plato.atr dist.atari/files
 
 ###################################################################
 ###  Place your additional targets in the additional Makefiles  ###