fix black with external link

Former-commit-id: b83c0d57c7401e27049353679f4f3e4b3bc9e981

README.md

@@ -1,6 +1,6 @@
 # Iris web framework
 
-<img align="right" width="105px" src="logo.svg" alt="Iris Logo: 2018" title="logo created by @merry.dii" />
+<img align="right" width="170px" src="https://iris-go.com/images/logo.svg" title="logo created by @merry.dii" />
 
 [![build status](https://img.shields.io/travis/kataras/iris/master.svg?style=flat-square)](https://travis-ci.org/kataras/iris) <!-- [![release](https://img.shields.io/github/release/kataras/iris.svg?style=flat-square)](https://github.com/kataras/iris/releases)--> [![report card](https://img.shields.io/badge/report%20card-a%2B-ff3333.svg?style=flat-square)](http://goreportcard.com/report/kataras/iris) [![github closed issues](https://img.shields.io/github/issues-closed-raw/kataras/iris.svg?style=flat-square)](https://github.com/kataras/iris/issues?q=is%3Aissue+is%3Aclosed) [![chat](https://img.shields.io/badge/community-%20chat-00BCD4.svg?style=flat-square)](https://kataras.rocket.chat/channel/iris) [![view examples](https://img.shields.io/badge/learn%20by-examples-0077b3.svg?style=flat-square)](https://github.com/kataras/iris/tree/master/_examples) [![release](https://img.shields.io/badge/release%20-v10.0-0077b3.svg?style=flat-square)](https://github.com/kataras/iris/releases)