Rethrow exception on MasterNodeManager StartUp (#1906)

* So far errors during startup of MasterNodeManager were consumed and only logged, so the app did not know there is an issue
* New behavior is to rethrow exception to retrieve it outside the NuGet package
* Update MasterNodeManager.cs

Libraries/Opc.Ua.Server/NodeManager/MasterNodeManager.cs

@@ -322,6 +322,7 @@ namespace Opc.Ua.Server
                     catch (Exception e)
                     {
                         Utils.LogError(e, "Unexpected error creating address space for NodeManager #{0}.", ii);
+                        throw;
                     }
                 }
 
@@ -337,6 +338,7 @@ namespace Opc.Ua.Server
                     catch (Exception e)
                     {
                         Utils.LogError(e, "Unexpected error adding references for NodeManager #{0}.", ii);
+                        throw;
                     }
                 }
             }