Fix ods export with doubles

Elwig/Helpers/Export/Ods.cs

@@ -264,8 +264,7 @@ namespace Elwig.Helpers.Export {
                 c = $"<{ct}{add}/>";
             } else if (data is float || data is double || data is byte || data is char ||
                        data is short || data is ushort || data is int || data is uint || data is long || data is ulong) {
-
-                double v = double.Parse(data?.ToString() ?? "0", CultureInfo.InvariantCulture);
+                double v = double.Parse(data?.ToString() ?? "0");  // use default culture for ToString and Parse()!
                 if (units != null && units.Length > 0) {
                     int n = -1;
                     switch (units[0]) {