removed incompatibility with sml

--- a/src/HOLCF/ROOT.ML	Tue Oct 17 16:53:29 1995 +0100
+++ b/src/HOLCF/ROOT.ML	Tue Oct 17 17:00:10 1995 +0100
@@ -28,12 +28,12 @@
 
 (* install sections: domain, generated *)
 
-use "domain/library";
-use "domain/syntax";
-use "domain/axioms";
-use "domain/theorems";
-use "domain/extender";
-use "domain/interface";
+use "domain/library.ML";
+use "domain/syntax.ML";
+use "domain/axioms.ML";
+use "domain/theorems.ML";
+use "domain/extender.ML";
+use "domain/interface.ML";
 
 init_thy_reader();
 init_pps ();