Vueify.Next: vue.config.js not loaded

In the current 'next' version, vue.config.js is ignored (in my case used for a custom compiler).

It seems that loading the file has been removed in this commit:

https://github.com/vuejs/vueify/commit/98ec0b2e2db1a05c83ef79a2378053bcd5185530#diff-168726dbe96b3ce427e7fedce31bb0bcL4

Is this a regression or is there a new mechanism for vue.config.js?
