preprocessor: remove unused filed histval_present from mod_file_struct

NumericalInitialization.cc

 /*
- * Copyright (C) 2003-2016 Dynare Team
+ * Copyright (C) 2003-2017 Dynare Team
  *
  * This file is part of Dynare.
  *
@@ -279,8 +279,6 @@ HistValStatement::HistValStatement(const hist_values_t &hist_values_arg,
 void
 HistValStatement::checkPass(ModFileStructure &mod_file_struct, WarningConsolidation &warnings)
 {
-  mod_file_struct.histval_present = true;
-
   if (all_values_required)
     {
       set<int> unused_endo = symbol_table.getEndogenous();

Statement.cc

 /*
- * Copyright (C) 2006-2015 Dynare Team
+ * Copyright (C) 2006-2017 Dynare Team
  *
  * This file is part of Dynare.
  *
@@ -40,7 +40,6 @@ ModFileStructure::ModFileStructure() :
   identification_present(false),
   estimation_analytic_derivation(false),
   partial_information(false),
-  histval_present(false),
   k_order_solver(false),
   calibrated_measurement_errors(false),
   dsge_prior_weight_in_estimated_params(false),

Statement.hh

 /*
- * Copyright (C) 2006-2015 Dynare Team
+ * Copyright (C) 2006-2017 Dynare Team
  *
  * This file is part of Dynare.
  *
@@ -72,9 +72,6 @@ public:
   bool estimation_analytic_derivation;
   //! Whether the option partial_information is given to stoch_simul/estimation/osr/ramsey_policy
   bool partial_information;
-  //! Whether a histval bloc is present
-  /*! Used for the workaround for trac ticket #157 */
-  bool histval_present;
   //! Whether the "k_order_solver" option is used (explictly, or implicitly if order >= 3)
   bool k_order_solver;
   //! Whether there is a calibrated measurement error