def unload_plugin(name)
      p = get_plugin(name)

      p.unload if p.respond_to?(:unload)
      Capistrano.remove_plugin(name)
    end
def unload_plugin(name)
      p = get_plugin(name)

      p.unload if p.respond_to?(:unload)
      Capistrano.remove_plugin(name)
    end
given a plugin name as a symbol, unload the capnotify plugin
 this will also unload any kind of capistrano plugin
 if the plugin supports the unload method, it will be called.