fix link to fehguy twitter account

Author: wing328

README.md

@@ -846,8 +846,8 @@ Here are some companies/projects using Swagger Codegen in production. To add you
 
 Presentations/Videos/Tutorials/Books
 ----------------------------------------
-- 2011/08/31 - [Introducing Swagger](https://www.slideshare.net/fehguy/introducing-swagger) by [Tony Tam](twitter.com/fehguy)
-- 2014/05/22 - [Swagger APIs for Humans and Robots](https://www.slideshare.net/fehguy/swagger-apis-for-humans-and-robots-gluecon) by [Tony Tam](twitter.com/fehguy) at [Gluecon](http://gluecon.com/)
+- 2011/08/31 - [Introducing Swagger](https://www.slideshare.net/fehguy/introducing-swagger) by [Tony Tam](https://twitter.com/fehguy)
+- 2014/05/22 - [Swagger APIs for Humans and Robots](https://www.slideshare.net/fehguy/swagger-apis-for-humans-and-robots-gluecon) by [Tony Tam](https://twitter.com/fehguy) at [Gluecon](http://gluecon.com/)
 - 2015/07/28 - [Enriching RESTful Services with Swagger](https://blog.philipphauer.de/enriching-restful-services-swagger/) by [Philipp Hauer](https://blog.philipphauer.de/)
 - 2015/11/11 - [Generate client stubs & document your REST-API using Swagger & Spring](https://www.youtube.com/watch?v=43GhBbP--oI) by [Johannes Fiala](https://github.com/jfiala) @ Devoxx Belgium 2015
 - 2015/12/03 - [こんなに簡単! Swagger Codegenのカスタマイズ](http://qiita.com/Quramy/items/c583f3213f0b77ff1bac) by [Quramy](http://qiita.com/Quramy)