Correct copy and paste mistake in comparison_policy_functions_dynare_mathematica.m

tests/decision_rules/third_order/comparison_policy_functions_dynare_mathematica.m

@@ -2,7 +2,7 @@
 if ~isoctave() && ~matlab_ver_less_than('8.4')
    websave('FV_2011_policyfunctions.mat','http://www.dynare.org/Datasets/FV_2011_policyfunctions.mat')
 else
-   urlwrite('http://www.dynare.org/Datasets/policyfunctions.mat','FV_2011_policyfunctions.mat')
+   urlwrite('http://www.dynare.org/Datasets/FV_2011_policyfunctions.mat','FV_2011_policyfunctions.mat')
 end
 
 load FV_2011_policyfunctions