Add back in migrations (sindresorhus#230)

Author: fregante

package.json

@@ -17,7 +17,7 @@
 	"dependencies": {
 		"delay": "^4.3.0",
 		"webext-base-css": "^1.1.0",
-		"webext-options-sync": "^1.2.0",
+		"webext-options-sync": "^1.2.4",
 		"webextension-polyfill": "^0.4.0"
 	},
 	"devDependencies": {

source/options-storage.js

@@ -10,7 +10,10 @@ const optionsStorage = new OptionsSync({
 		reuseTabs: false,
 		updateCountOnNavigation: false,
 		filterNotifications: false
-	}
+	},
+	migrations: [
+		OptionsSync.migrations.removeUnused
+	]
 });
 
 export default optionsStorage;