Add startup template file

Author: rasmusjp

src/Our.Umbraco.GraphQL/content/App_Start/GraphQLConfig.cs.pp

@@ -0,0 +1,16 @@
+using Umbraco.Core;
+using Umbraco.Web;
+
+using Our.Umbraco.GraphQL.Web;
+
+namespace $rootnamespace$
+{
+    public class GraphQLConfig : ApplicationEventHandler
+    {
+        protected override void ApplicationStarted(UmbracoApplicationBase umbracoApplication, ApplicationContext applicationContext)
+        {
+            UmbracoDefaultOwinStartup.MiddlewareConfigured += (sender, e) =>
+                e.AppBuilder.UseUmbracoGraphQL(applicationContext, new GraphQLServerOptions());
+        }
+    }
+}