Update promisify.md

snippets/promisify.md

@@ -1,6 +1,9 @@
 ### Promisify
 
-Use currying to return a function returning a Promise that calls the original function. Use the rest operator to pass in all the parameters. In Node 8+, you can use [`util.promisify`](https://nodejs.org/api/util.html#util_util_promisify_original)
+Use currying to return a function returning a `Promise` that calls the original function. 
+Use the `...rest` operator to pass in all the parameters. 
+
+*In Node 8+, you can use [`util.promisify`](https://nodejs.org/api/util.html#util_util_promisify_original)*
 
 ```js
 const promisify = func =>