Adding ESLint config and required dev dependencies

.eslintignore

@@ -0,0 +1,5 @@
+**/webpack.config.js
+lib/**
+runner/dist/**
+src/testdata/**
+tests/**

.eslintrc.json

@@ -0,0 +1,32 @@
+
+{
+    "parser": "@typescript-eslint/parser",
+    "parserOptions": {
+      "project": "./tsconfig.json"
+    },
+    "plugins": ["@typescript-eslint", "filenames", "github", "import", "no-async-foreach"],
+    "extends": [
+      "eslint:recommended",
+      "plugin:@typescript-eslint/recommended",
+      "plugin:@typescript-eslint/recommended-requiring-type-checking",
+      "plugin:github/recommended",
+      "plugin:github/typescript"
+    ],
+    "rules": {
+      "filenames/match-regex": ["error", "^[a-z0-9-]+(\\.test)?$"],
+      "import/extensions": "error",
+      "import/no-amd": "error",
+      "import/no-commonjs": "error",
+      "import/no-dynamic-require": "error",
+      "import/no-extraneous-dependencies": ["error", {"devDependencies": false}],
+      "import/no-namespace": "off",
+      "import/no-unresolved": "error",
+      "import/no-webpack-loader-syntax": "error",
+      "no-async-foreach/no-async-foreach": "error",
+      "no-console": "off",
+      "no-sequences": "error",
+      "one-var": ["error", "never"],
+      "sort-imports": ["error", { "allowSeparatedGroups": true }]
+    }
+  }
+