[math] Include functional header for std::reference_wrapper

Author: dpiparo

roofit/roofitcore/inc/RooCmdConfig.h

@@ -1,7 +1,7 @@
 /*****************************************************************************
  * Project: RooFit                                                           *
  * Package: RooFitCore                                                       *
- *    File: $Id: RooCmdConfig.h,v 1.12 2007/05/11 09:11:30 verkerke Exp $
+ *    File: $Id: RooCmdConfig.h,v 1.12 2007/05/11 09:11:30 verkerke Exp $    *
  * Authors:                                                                  *
  *   WV, Wouter Verkerke, UC Santa Barbara, [email protected]       *
  *   DK, David Kirkby,    UC Irvine,         [email protected]                 *
@@ -25,6 +25,7 @@
 #include <TObject.h>
 #include <TString.h>
 
+#include <functional>
 #include <string>
 
 class RooArgSet;