[Core] Initialize FeatureSwitchService on the common Runtime init

Author: Rodrigo Moya

main/src/core/MonoDevelop.Core/MonoDevelop.Core.FeatureConfiguration/FeatureSwitchService.cs

@@ -37,7 +37,7 @@ public static class FeatureSwitchService
 	{
 		static Dictionary<string, FeatureSwitch> featureSwitches = new Dictionary<string, FeatureSwitch> ();
 
-		static FeatureSwitchService ()
+		internal static void Initialize ()
 		{
 			AddinManager.AddExtensionNodeHandler ("/MonoDevelop/Core/FeatureSwitches", HandleFeatureSwitchExtension);
 		}

main/src/core/MonoDevelop.Core/MonoDevelop.Core/Runtime.cs

@@ -42,6 +42,7 @@
 using Mono.Addins.Setup;
 using MonoDevelop.Core.Assemblies;
 using MonoDevelop.Core.Execution;
+using MonoDevelop.Core.FeatureConfiguration;
 using MonoDevelop.Core.Instrumentation;
 using MonoDevelop.Core.Setup;
 using MonoDevelop.Core.Web;
@@ -144,6 +145,9 @@ public static void Initialize (bool updateAddinRegistry)
 				systemAssemblyService = new SystemAssemblyService ();
 				systemAssemblyService.Initialize ();
 				LoadMSBuildLibraries ();
+
+				// Initialize extra services
+				FeatureSwitchService.Initialize ();
 
 				initialized = true;