chore: fix husky configuration

apprently, husky has recently changed their configuration format, and for that reason our pre-commit hook was never running. The following blog posts explain the change in depth:

* https://blog.typicode.com/husky-git-hooks-javascript-config/
* https://blog.typicode.com/husky-git-hooks-autoinstall/

This commit fixes the husky configuration + upgrades husky to 6.0.0, so
now prettier / eslint should run again before every commit,
automatically.

.husky/.gitignore

@@ -0,0 +1 @@
+_

.husky/pre-commit

@@ -0,0 +1,4 @@
+#!/bin/sh
+. "$(dirname "$0")/_/husky.sh"
+
+npx lint-staged

package.json

@@ -25,6 +25,7 @@
   "scripts": {
     "build": "rimraf dist && tsc && tsc -p tsconfig.esm.json && node build-scripts/dist-package-json",
     "prepublish": "npm run build",
+    "prepare": "husky install",
     "lint": "eslint . --ext .ts",
     "start": "ts-node demo/emulator-run.ts",
     "start:micropython": "ts-node demo/micropython-run.ts",
@@ -37,7 +38,7 @@
     "@typescript-eslint/eslint-plugin": "^4.22.1",
     "@typescript-eslint/parser": "^4.22.1",
     "eslint": "^7.26.0",
-    "husky": "^5.1.1",
+    "husky": "^6.0.0",
     "jest": "^26.6.3",
     "lint-staged": "^11.0.0",
     "prettier": "^2.2.1",
@@ -48,15 +49,10 @@
     "typescript": "^4.1.3"
   },
   "lint-staged": {
-    "src/**/*.ts": [
+    "**/*.{js,ts}": [
       "eslint --fix",
       "prettier --write",
       "git add"
     ]
-  },
-  "husky": {
-    "hooks": {
-      "pre-commit": "lint-staged"
-    }
   }
 }