Merge pull request tweenjs#652 from christjt/christjt/package-health

fix(package.json): add export map

Author: trusktr

package.json

@@ -6,6 +6,12 @@
 	"main": "dist/tween.cjs.js",
 	"types": "dist/tween.d.ts",
 	"module": "dist/tween.esm.js",
+	"exports": {
+		".": {
+			"import": "./dist/tween.esm.js",
+			"require": "./dist/tween.cjs.js"
+		}
+	},
 	"files": [
 		"dist",
 		"README.md",