给webpack前端工程添加.eslintrc和.editorconfig

[valleylmh]

1、增加.eslintrc文件，需要安装如下npm包：

"babel-eslint": "^8.2.3",
    "eslint": "^4.19.1",
    "eslint-config-standard": "^11.0.0",
    "eslint-loader": "^2.0.0",
    "eslint-plugin-html": "^4.0.3",
    "eslint-plugin-import": "^2.12.0",
    "eslint-plugin-node": "^6.0.1",
    "eslint-plugin-promise": "^3.7.0",
    "eslint-plugin-standard": "^3.1.0",

2、增加.editorconfig文件，代码编辑器需要按照插件