proper use_thy;

--- a/src/Pure/ROOT.ML	Tue Apr 05 15:58:58 2016 +0200
+++ b/src/Pure/ROOT.ML	Tue Apr 05 17:16:46 2016 +0200
@@ -335,5 +335,6 @@
 use "Tools/jedit.ML";
 
 use_thy "Pure";
+use_thy "ML/ML_Root";
 
 use "ML/ml_pervasive_final.ML";