Document how to disable/customize the prefetch plugin

What problem does this feature solve?

When I use the asyn load of vue-router, the webpack-plugin prefetch makes all asyn modules preload. This results in the inability to load on demand

What does the proposed API look like?

vue.conf.js

{
  prefetch: {}
}

[LinusBorg]

Thanks @Dealerpriest, that was very helpful.

This can be custimzed with webpack-chain today like this:

// vue.config.js
chainWebpack: (config) => {

  // A, remove the plugin
  config.plugins.delete('prefetch')
  
  // or:
  // B. Alter settings:
  config.plugin('prefetch').tap(options => {
    if (!options[0].fileBlacklist) options[0].fileBlacklist = []
    options[0].fileBlacklist.push(/myasyncRoute(.)+?\.js$/)
    return options
  })
}

Relevant source: https://github.com/vuejs/vue-cli/blob/dev/packages/%40vue/cli-service/lib/config/app.js#L20-L25

We can discuss wether or not it makes sense to expose this as a config value in vue.config.js

[wangxiangyao]

我需要使用webpack-chain，来重新配置Prefetch，对么？