Bugfix for RpsAddins without startup scripts

Author: daren-thomas

Output/2016.06.29_Setup_RevitPythonShell_2017.exe

@@ -1,7 +1,7 @@
 
 Microsoft Visual Studio Solution File, Format Version 12.00
 # Visual Studio 2013
-VisualStudioVersion = 12.0.40629.0
+VisualStudioVersion = 12.0.21005.1
 MinimumVisualStudioVersion = 10.0.40219.1
 Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "RevitPythonShell", "RevitPythonShell\RevitPythonShell.csproj", "{7E37F14E-D840-42F8-8CA6-90FFC5497972}"
 EndProject

RevitPythonShell.sln

@@ -198,6 +198,10 @@ private void ExecuteStartupScript(UIControlledApplication uiControlledApplicatio
         /// </summary>
         private string GetEmbeddedScript(string scriptName, Assembly addinAssembly)
         {         
+            if (scriptName == null)
+            {
+                return null;
+            }
             var source = new StreamReader(addinAssembly.GetManifestResourceStream(scriptName)).ReadToEnd();
             return source;
         }