[mod] SearXNG JavaScript Style Guide (eslint:recommended)

The SearXNG JavaScript Style Guide is a set of eslint rules [1] based on the
eslint:recommended [2] rules.

    "extends": "eslint:recommended"

The additional rules adopted from the JavaScript Standard Style [3][4].

[1] https://eslint.org/docs/rules/
[2] https://github.com/kunalgolani/eslint-config/tree/master/packages/recommended
[3] https://standardjs.com/rules.html#javascript-standard-style
[4] https://github.com/standard/eslint-config-standard/blob/master/.eslintrc.json

Signed-off-by: Markus Heiser <markus.heiser@darmarit.de>

searx/static/themes/simple/gruntfile.js

@@ -27,7 +27,8 @@ module.exports = function(grunt) {
     eslint: {
       options: {
         overrideConfigFile: '.eslintrc.json',
-        failOnError: false
+        failOnError: false,
+        fix: grunt.option('fix')
       },
       target: [
         'svg4web.svgo.js',