fix all the cases, much white noise, array to list, string to sym stuff

test/cases/return/return_int.tst

@@ -1,4 +1,5 @@
 return 42
 -- -- --
-s(:list,  [s(:return, 
-  s(:int,  42))])
+s(:expressions, 
+  s(:return, 
+    s(:int,  42)))

test/cases/return/return_string.tst

@@ -1,4 +1,5 @@
 return "hello"
 -- -- --
-s(:list,  [s(:return, 
-  s(:string,  "hello"))])
+s(:expressions, 
+  s(:return, 
+    s(:string,  "hello")))

test/cases/return/return_variable.tst

@@ -1,4 +1,5 @@
 return foo
 -- -- --
-s(:list,  [s(:return, 
-  s(:name,  "foo"))])
+s(:expressions, 
+  s(:return, 
+    s(:name,  :foo)))