adding examples and modifying parameter descriptions

[zhenzhenChange]

document: src/api/global-api.md

Modified api:

• defineAsyncComponent

  Advanced Usage, Adding examples to the onError hook (Reference rfc) :

  ...
  onError(error, retry, fail, attempts) {
    if (error.message.match(/fetch/) && attempts <= 3) {
      // retry on fetch errors, 3 max attempts
      retry()
    } else {
      // Note that retry/fail are like resolve/reject of a promise:
      // one of them must be called for the error handling to continue.
      fail()
    }
  }
  ...

• resolveComponent

  Modify parameter descriptions:

  Accepts one argument: `component` --> Accepts one argument: `name`

[skirtles-code]

I believe this has been fixed in #523.