worked on function call return type check and started checking return type

tests/sprint2/test/sp2_sp2_arrayargs.alpha

@@ -0,0 +1,16 @@
+type string: 1 -> character
+type a_of_s: 1 -> string
+
+(* maybe some other type definitions *)
+
+entry(arg) := {
+    [ string: one_name; string: another_name; a_of_s: many_names ]
+    another_name := reserve another_name(4); (* reserve space for an an array of character, with 4 members *)
+    many_names := reserve a_of_s(many_names);
+    many_names(0) := one_name;
+    many_names(1) := another_name;
+    many_names(2) := reserve a_of_s(2)(6); (* reserve space for an item of the same type as a_of_s(2), an array of character, with 6 members *)
+    many_names(2)(0) := "P";
+    
+    return 0;
+}