If the addin cannot be properly loaded, just skip the file. (#11)

Author: anshivashankar

DesignAutomationHandler.cs

@@ -19,7 +19,17 @@ public Result Execute(ExternalCommandData commandData, ref string message, Eleme
             string[] files = Directory.GetFiles(app.AllUsersAddinsLocation, "*.addin");
             foreach (string file in files)
             {
-               XElement addin = XElement.Load(file);
+               XElement addin;
+               try
+               {
+                  addin = XElement.Load(file);
+               }
+               catch
+               {
+                  MessageBox.Show($"Malformed XML in addin: {file}", "DesignAutomationHandler");
+                  // if the XML is malformed or not parse-able, just continue
+                  continue;
+               }
                IEnumerable<XElement> childList = from el in addin.Elements() select el;
                foreach (XElement e in childList)
                {