change test framework to use files for in and out (s-exp)

test/cases/compound/hash_list.tst

@@ -0,0 +1,7 @@
+{foo => 33 , bar => 42}
+-- -- --
+s(:list,  [s(:hash,  [s(:assoc, 
+  s(:name,  "foo"), 
+  s(:int,  33)), s(:assoc, 
+  s(:name,  "bar"), 
+  s(:int,  42))])])