demoChallenge: minimal demo grammar

isr-grammar/english/ToBI_DEMO_CHALLENGE/ToBI_DEMO_CHALLENGE.grm

 $$S: $confirm_yes
-	| $confirm_no 
-	| $stop 
-	| $stopPlaying
-	| $startPlaying
-	| tobi $yourTurn;
+	| $confirm_no
+	| $smalltalk;
 
-$yourTurn: its your turn
-		| it is your turn;
-		
-$stopPlaying: lets stop here
-			| lets stop playing
-			| let us stop here
-			| let us stop playing;
-			
-$startPlaying: let us play a game
-			| let us play
-			| lets play a game
-			| lets play;
-
-$stop: stop;
+$smalltalk: joke
+		| time;
 
 $confirm_yes: tobi please
 		| tobi yes