rustc: Move fold to rustsyntax

Author: brson

src/rustc/syntax/fold.rs renamed to src/librustsyntax/fold.rs

@@ -1,4 +1,4 @@
-import syntax::codemap::span;
+import codemap::span;
 import ast::*;
 
 export ast_fold_precursor;

src/librustsyntax/rustsyntax.rc

@@ -10,6 +10,7 @@ mod codemap;
 mod ast;
 mod ast_util;
 mod visit;
+mod fold;
 mod util {
     mod interner;
 }

src/rustc/rustc.rc

@@ -70,7 +70,6 @@ mod middle {
 
 
 mod syntax {
-    mod fold;
     mod parse {
         mod lexer;
         mod parser;

src/rustc/syntax.rs

@@ -11,6 +11,9 @@ export ast_util;
 import rustsyntax::visit;
 export visit;
 
+import rustsyntax::fold;
+export fold;
+
 export ast;
 export ast_util;
 export visit;