Add a way to set global config

[muuvmuuv]

It would be great if I could set some global options by default like appName on the start of my task notifier. This would prevent me to merge objects every time or assign the values new.

Maybe I miss something out but my way ATM is:

const notifierOptions = {
  appName: APP_NAME,
  title: APP_NAME,
  message: 'Starting gulp...',
  sound: true,
}

notifierOptions.message = `Starting compressing files for ${name}`
src(file).pipe(notify(notifierOptions))

would be great if I could just

notify.appName = APP_NAME