Add size demo

demos/size.tri

@@ -0,0 +1,19 @@
+compose = (\f g x : f (g x))
+
+succ = y (\self : 
+  triage 
+    1 
+    t 
+    (triage 
+      (t (t t)) 
+      (\_ tail : t t (self tail)) 
+      t))
+
+size = (\x : 
+  (y (\self x : 
+    compose succ 
+      (triage 
+        (\x : x) 
+        self 
+        (\x y : compose (self x) (self y)) 
+        x)) x 0))

demos/toSource.tri

@@ -43,4 +43,4 @@ toSource_ = y (\self arg :
 toSource = (\v : toSource_ v "")
 
 exampleOne = toSource true -- OUT: "(t t)"
-exampleTwo = toSource not  -- OUT: "(t (t (t t) (t t t)) (t t (t t t)))"
+exampleTwo = toSource not?  -- OUT: "(t (t (t t) (t t t)) (t t (t t t)))"