META: upgrade to vue cli 3 environment

.babelrc

.editorconfig

.env.development

.env.production

.eslintignore

.eslintrc.js

.gitignore

.postcssrc.js

README.md

babel.config.js

build/build.js

build/check-versions.js

build/dev-client.js

build/dev-server.js

build/utils.js

build/vue-loader.conf.js

build/webpack.base.conf.js

build/webpack.dev.conf.js

build/webpack.prod.conf.js

build/webpack.test.conf.js