Move utilities into own directory.

TODO: There are more functions which may be migrated into dom and string.

generators/python.js

@@ -27,6 +27,7 @@
 goog.provide('Blockly.Python');
 
 goog.require('Blockly.Generator');
+goog.require('Blockly.utils.string');
 
 
 /**
@@ -254,7 +255,8 @@ Blockly.Python.scrub_ = function(block, code, opt_thisOnly) {
   if (!block.outputConnection || !block.outputConnection.targetConnection) {
     // Collect comment for this block.
     var comment = block.getCommentText();
-    comment = Blockly.utils.wrap(comment, Blockly.Python.COMMENT_WRAP - 3);
+    comment = Blockly.utils.string.wrap(comment,
+        Blockly.Python.COMMENT_WRAP - 3);
     if (comment) {
       if (block.getProcedureDef) {
         // Use a comment block for function comments.