[meta] add version scripts

.npmrc

@@ -1 +1,3 @@
 package-lock=false
+allow-same-version=true
+message=v%s

package.json

@@ -4,6 +4,8 @@
 	"description": "Does this JS environment support the `name` property on functions?",
 	"main": "index.js",
 	"scripts": {
+		"version": "auto-changelog && git add CHANGELOG.md",
+		"postversion": "auto-changelog && git add CHANGELOG.md && git commit --no-edit --amend && git tag -f \"v$(node -e \"console.log(require('./package.json').version)\")\"",
 		"lint": "eslint .",
 		"pretest": "npm run lint",
 		"tests-only": "node test",
@@ -30,7 +32,14 @@
 	"homepage": "https://github.com/ljharb/functions-have-names#readme",
 	"devDependencies": {
 		"@ljharb/eslint-config": "^13.1.1",
+		"auto-changelog": "^1.14.1",
 		"eslint": "^5.16.0",
 		"tape": "^4.11.0"
+	},
+	"auto-changelog": {
+		"output": "CHANGELOG.md",
+		"unreleased": false,
+		"commitLimit": false,
+		"backfillLimit": false
 	}
 }