Update `after` call to work with capistrano3.5
Update `after` call to work with capistrano3.5

Capistrano 3.5 changes the way `after` hooks are called
to ensure they are namespace aware, see https://github.com/capistrano/capistrano/blob/master/CHANGELOG.md
and https://github.com/capistrano/capistrano/issues/1652

platanus/capistrano3-nginx,platanus/capistrano3-nginx