Updated model link to correct one (#215)

Author: M-ZubairAhmed

README.md

@@ -31,7 +31,7 @@ $ go get github.com/netlify/open-api/...
 
 - [Porcelain](https://godoc.org/github.com/netlify/open-api/go/porcelain): High level interactions and operations
 - [Plumbing](https://godoc.org/github.com/netlify/open-api/go/plumbing): Low level client operations generated by [go-swagger][go-swagger]
-- [Models](https://godoc.org/github.com/netlify/open-api/go/porcelain): Models generated by [go-swagger][go-swagger]
+- [Models](https://godoc.org/github.com/netlify/open-api/go/models): Models generated by [go-swagger][go-swagger]
 
 See [CONTRIBUTING.md](CONTRIBUTING.md) for details on how this client is developed and generated.