code: func (m *Manager) Register(name string, plugin Plugin) {
  	m.mtx.Lock()
  	defer m.mtx.Unlock()
  	m.plugins = append(m.plugins, namedplugin{
  		name:   name,
  		plugin: plugin,
  	})
  }
docs: // Register adds a plugin to the manager. When the manager is started, all of
  // the plugins will be started.