rename back to plugins

https://github.com/senecajs/seneca/blob/1c97c5fba6f4e3c61b037be42656036a83321b36/seneca.js#L468


  root$.order = {}

  // TODO: rename back to plugins
  const api_use = Plugin.api_use(callpoint, { debug: !!start_opts.debug.ordu })
  root$.order.plugin = api_use.ordu

  // Seneca methods. Official API.
  root$.toString = API.toString
  root$.has = API.has // True if the given pattern has an action.

senecajs / seneca

rename back to plugins #852