[plt-translators] english-string-constants.ss update

Index: $PLTHOME/collects/string-constants/english-string-constants.ss
===================================================================
--- $PLTHOME/collects/string-constants/english-string-constants.ss	(revision 15992)
+++ $PLTHOME/collects/string-constants/english-string-constants.ss	(working copy)
@@ -711,6 +711,7 @@
   
  (user-defined-keybinding-error "Error running keybinding ~a\n\n~a")
  (user-defined-keybinding-malformed-file "The file ~a does not contain a module written in the framework/keybinding-lang language.")  
+ (user-defined-keybinding-malformed-file/found-lang "The file ~a does not contain a module written in the framework/keybinding-lang language. Instead, found the language ~s")  
   
  ;; menu items in the "special" menu
  (insert-text-box-item "Insert Text Box")