Add prepublishOnly script

Author: marvinhagemeister

package.json

@@ -11,7 +11,8 @@
 		"lint": "eslint src/*.js",
 		"test": "karmatic",
 		"test:browser": "MOZ_HEADLESS=1 karmatic --no-coverage --browsers chrome:headless,firefox,sauce-safari",
-		"prettier": "prettier **/*.js --write"
+		"prettier": "prettier **/*.js --write",
+		"prepublishOnly": "npm run lint && npm run test"
 	},
 	"eslintConfig": {
 		"extends": "developit",