Temporarily circumvent duplicate 'Define Names' problem introduced by Google Sheets .xlsx export bug.

EPPlus/ExcelNamedRangeCollection.cs

diff --git a/EPPlus/ExcelNamedRangeCollection.cs b/EPPlus/ExcelNamedRangeCollection.cs
index 3f6a493..537a7db 100644
--- a/EPPlus/ExcelNamedRangeCollection.cs
+++ b/EPPlus/ExcelNamedRangeCollection.cs
@@ -91,10 +91,12 @@
                     if ((listItem != null) && (listItem.FullAddress == item.FullAddress))
                         return;
 
-                    throw new Exception(string.Format("Name '{0}' is defined in the worksheet more than once. First as '{1}' and second as '{2}'.", Name, listItem.FullAddress, item.FullAddress));
+                    //throw new Exception(string.Format("Name '{0}' is defined in the worksheet more than once. First as '{1}' and second as '{2}'.", Name, listItem.FullAddress, item.FullAddress));
+                    return;
                 }
 
-                throw new Exception(string.Format("Name '{0}' is defined in the worksheet more than once.", Name));
+                //throw new Exception(string.Format("Name '{0}' is defined in the worksheet more than once.", Name));
+                return;
             }
 
             _dic.Add(Name, _list.Count);