Another baseurl related fix

Baseurl always starts with a '/' (unless it's empty)

Emby.Server.Implementations/ApplicationHost.cs

@@ -1522,7 +1522,7 @@ namespace Emby.Server.Implementations
             string baseUrl = ServerConfigurationManager.Configuration.BaseUrl;
             if (baseUrl.Length != 0)
             {
-                url.Append('/').Append(baseUrl);
+                url.Append(baseUrl);
             }
 
             return url.ToString();