Add support for loading WebAssembly and ES Modules

[ScreamZ]

Hello,

It is pretty common to see .wasm and .mjs files nowadays, some library start using them and this break by default in vue-cli without extending like this.

This pull request add support for those kind of files out-of-the-box.

vue.config.js

module.exports = {
  chainWebpack: config => config.resolve.extensions.prepend('.mjs').prepend('.wasm')
}

Do not hesitate to ping me if you have any questions / need something.

Regards

[haoqunjiang]

As a side note: jest currently does not support these extensions (jestjs/jest#4842). We should document it somewhere.

See also react/create-react-app#5258 (comment)

[ScreamZ]

@sodatea What do you think of here ?

[haoqunjiang]

@ScreamZ Looks good to me.