Add TypeScript, ESLint, and prettier

Author: devknoll

.eslintignore

@@ -0,0 +1 @@
+build/

.eslintrc.json

@@ -0,0 +1,11 @@
+{
+  "root": true,
+  "env": {
+    "browser": true,
+    "es6": true,
+    "node": true
+  },
+  "parser": "@typescript-eslint/parser",
+  "plugins": ["@typescript-eslint"],
+  "extends": ["eslint:recommended", "plugin:@typescript-eslint/recommended"]
+}

.gitignore

@@ -1,4 +1,2 @@
-cqfill.js
-cqfill.min.js
-cqfill.iife.min.js
+build
 node_modules

.prettierignore

@@ -0,0 +1,2 @@
+build/
+tests/*.html

.prettierrc.json

@@ -0,0 +1,6 @@
+{
+  "bracketSpacing": false,
+  "singleQuote": true,
+  "trailingComma": "es5",
+  "arrowParens": "avoid"
+}

README.md

@@ -7,9 +7,9 @@ A tiny polyfill for [CSS Container Queries][mdn], weighing about 1.6kB brotli’
 Ideally, the polyfill is only loaded if the browser doesn’t support Container Queries natively. In a modern setup with a bundler that uses ES modules, the following snippet should work:
 
 ```js
-const supportsContainerQueries = "container" in document.documentElement.style;
+const supportsContainerQueries = 'container' in document.documentElement.style;
 if (!supportsContainerQueries) {
-  import("container-query-polyfill");
+  import('container-query-polyfill');
 }
 ```