Setup Castle Windsor for Sitecore 8.1

SetupIoc.config

<?xml version="1.0"?>
<configuration>
  <sitecore>
    <pipelines>
      <initialize>
        <processor type="Website.SetupIoc, Website" />
      </initialize>
    </pipelines>
  </sitecore>
</configuration>

SetupIoc.cs

using System.Web.Mvc;
using Castle.MicroKernel.Registration;
using Castle.Windsor;
using CommonServiceLocator.WindsorAdapter;
using Sitecore.Pipelines;

namespace Website
{
    public class SetupIoc
    {
        public void Process(PipelineArgs args)
        {
            var container = new WindsorContainer();
            container.Register(Classes.FromThisAssembly().BasedOn<IController>().LifestyleTransient());
            DependencyResolver.SetResolver(new WindsorServiceLocator(container));
        }
    }
}