[suggestion] merge weex-vue-loader & vue-loader together

[Jinjiang]

In vue-loader we hope to:

1. build weex js bundle through app.vue?platform=weex
2. automatically call new Vue({ el: '#app', ...options }) through app.vue?el=#app in order to delete entry js file
3. even output both weex js bundle and web js bundle just like [name]-[platform].js in one webpack task through app.vue?platform=all (is that possible?)

[yyx990803]

Can we list out the differences between the web build and weex build? (i.e. what is currently different in weex-vue-loader?)