update won't fail if service can't be stopped.

NzbDrone.Update/Providers/UpdateProvider.cs

@@ -54,9 +54,17 @@ namespace NzbDrone.Update.Providers
                && _serviceProvider.IsServiceRunning(ServiceProvider.NZBDRONE_SERVICE_NAME))
             {
                 appType = AppType.Service;
+
+                try
+                {
                     _serviceProvider.Stop(ServiceProvider.NZBDRONE_SERVICE_NAME);
-            }
 
+                }
+                catch (InvalidOperationException e)
+                {
+                    logger.WarnException("couldn't stop service", e);
+                }
+            }
             else
             {
                 appType = AppType.Normal;

NzbDrone/Owin/OwinHostController.cs

@@ -1,10 +1,7 @@
 using System;
 using System.Collections.Generic;
-using System.Threading.Tasks;
 using Microsoft.Owin.Hosting;
 using NLog;
-using Nancy.Bootstrapper;
-using Nancy.Owin;
 using NzbDrone.Common;
 using NzbDrone.Owin.MiddleWare;
 using Owin;