Fixed issue with xls files.

Octave cannot read xls files, download xlsx files instead.

(cherry picked from commit 436551db)

src/@dseries/dseries.m

@@ -391,12 +391,21 @@ end % classdef
 
 %@test:9
 %$ try
-%$     [strfile, status] = urlwrite('http://www.dynare.org/Datasets/dseries/dynseries_test_data-1.xlsx','dynseries_test_data-1.xlsx');
+%$     if isoctave()
+%$         [strfile, status] = urlwrite('http://www.dynare.org/Datasets/dseries/dynseries_test_data-1.xlsx','dynseries_test_data-1.xlsx');
+%$     else
+%$         [strfile, status] = urlwrite('http://www.dynare.org/Datasets/dseries/dynseries_test_data-1.xls','dynseries_test_data-1.xls');
+%$     end
 %$     if ~status
 %$         error()
 %$     end
-%$     ts = dseries('dynseries_test_data-1.xlsx');
-%$     delete('dynseries_test_data-1.xlsx');
+%$     if isoctave()
+%$         ts = dseries('dynseries_test_data-1.xlsx');
+%$         delete('dynseries_test_data-1.xlsx');
+%$     else
+%$         ts = dseries('dynseries_test_data-1.xls');
+%$         delete('dynseries_test_data-1.xls');
+%$     end
 %$     t(1) = 1;
 %$ catch
 %$     t(1) = 0;
@@ -417,12 +426,21 @@ end % classdef
 
 %@test:10
 %$ try
-%$     [strfile, status] = urlwrite('http://www.dynare.org/Datasets/dseries/dynseries_test_data-2.xlsx','dynseries_test_data-2.xlsx');
+%$     if isoctave()
+%$         [strfile, status] = urlwrite('http://www.dynare.org/Datasets/dseries/dynseries_test_data-2.xlsx','dynseries_test_data-2.xlsx');
+%$     else
+%$         [strfile, status] = urlwrite('http://www.dynare.org/Datasets/dseries/dynseries_test_data-2.xls','dynseries_test_data-2.xls');
+%$     end
 %$     if ~status
 %$         error()
 %$     end
-%$     ts = dseries('dynseries_test_data-2.xlsx');
-%$     delete('dynseries_test_data-2.xlsx');
+%$     if isoctave()
+%$         ts = dseries('dynseries_test_data-2.xlsx');
+%$         delete('dynseries_test_data-2.xlsx');
+%$     else
+%$         ts = dseries('dynseries_test_data-2.xls');
+%$         delete('dynseries_test_data-2.xls');
+%$     end
 %$     t(1) = 1;
 %$ catch
 %$     t(1) = 0;
@@ -443,12 +461,21 @@ end % classdef
 
 %@test:11
 %$ try
-%$     [strfile, status] = urlwrite('http://www.dynare.org/Datasets/dseries/dynseries_test_data-3.xlsx','dynseries_test_data-3.xlsx');
+%$     if isoctave()
+%$         [strfile, status] = urlwrite('http://www.dynare.org/Datasets/dseries/dynseries_test_data-3.xlsx','dynseries_test_data-3.xlsx');
+%$     else
+%$         [strfile, status] = urlwrite('http://www.dynare.org/Datasets/dseries/dynseries_test_data-3.xls','dynseries_test_data-3.xls');
+%$     end
 %$     if ~status
 %$         error()
 %$     end
-%$     ts = dseries('dynseries_test_data-3.xlsx');
-%$     delete('dynseries_test_data-3.xlsx');
+%$     if isoctave()
+%$         ts = dseries('dynseries_test_data-3.xlsx');
+%$         delete('dynseries_test_data-3.xlsx');
+%$     else
+%$         ts = dseries('dynseries_test_data-3.xls');
+%$         delete('dynseries_test_data-3.xls');
+%$     end
 %$     t(1) = 1;
 %$ catch
 %$     t(1) = 0;
@@ -469,12 +496,21 @@ end % classdef
 
 %@test:12
 %$ try
-%$     [strfile, status] = urlwrite('http://www.dynare.org/Datasets/dseries/dynseries_test_data-4.xlsx','dynseries_test_data-4.xlsx');
+%$     if isoctave()
+%$         [strfile, status] = urlwrite('http://www.dynare.org/Datasets/dseries/dynseries_test_data-4.xlsx','dynseries_test_data-4.xlsx');
+%$     else
+%$         [strfile, status] = urlwrite('http://www.dynare.org/Datasets/dseries/dynseries_test_data-4.xls','dynseries_test_data-4.xls');
+%$     end
 %$     if ~status
 %$         error()
 %$     end
-%$     ts = dseries('dynseries_test_data-4.xlsx');
-%$     delete('dynseries_test_data-4.xlsx');
+%$     if isoctave()
+%$         ts = dseries('dynseries_test_data-4.xlsx');
+%$         delete('dynseries_test_data-4.xlsx');
+%$     else
+%$         ts = dseries('dynseries_test_data-4.xls');
+%$         delete('dynseries_test_data-4.xls');
+%$     end
 %$     t(1) = 1;
 %$ catch
 %$     t(1) = 0;