Update ZEIT Now -> Vercel (#1525)

README.md

@@ -80,7 +80,7 @@ To translate Excalidraw into other languages, please visit [our Crowdin page](ht
 - [React](https://reactjs.org)
 - [Rough.js](https://roughjs.com)
 - [TypeScript](https://typescriptlang.org)
-- [ZEIT Now](https://zeit.co)
+- [Vercel](https://vercel.com)
 
 And the main source of inspiration for starting the project is the awesome [Zwibbler](https://zwibbler.com/demo/) app.