added tests for assignable and memory

tests/sprint2/test/test_carls_mistake.alpha

@@ -0,0 +1,27 @@
+type rec: [integer: x; integer: y]
+type T1: integer -> integer
+type T2: rec -> integer
+
+function foo : T1
+function bar1 : T2
+function bar2 : T2
+
+foo(x) := {
+        return x * x;
+}
+bar1(a) := {
+	 return a.x * a.y;
+}
+bar2 as (r,s) := {
+     return r * s;
+}
+entry(arg) := {
+ 	   [ integer: result ; rec: w]
+ 	   result := foo(5);
+ 	   w := reserve(w); (* see types.alpha – reserve returns a value of type address, which can be assigned to array and record variables*)
+	   w.x := 5;
+ 	   w.y := 7;
+ 	   result := bar1(w); (* pass w (a rec type value) to bar1 *)
+ 	   result := bar2(5,7); (* implicitly build a rec type value, assign 5 and 7 to fields x and y, but call them r and s *)
+ 	   return 0;
+}