fix more gitbook links

relates to #97

README.md

@@ -15,13 +15,13 @@ way_.
 We assume you’re familiar with the basics of HTTP+JSON APIs and won’t
 cover all of the fundamentals of those in this guide.
 
-Available for online reading and in multiple formats at [gitbook](https://www.gitbook.com/read/book/geemus/http-api-design).
+Available for online reading and in multiple formats at [gitbook](https://geemus.gitbooks.io/http-api-design/).
 
 We welcome [contributions](https://github.com/interagent/http-api-design/blob/master/CONTRIBUTING.md) to this guide.
 
 See [Summary](en/SUMMARY.md) for Table of Contents.
 
-For the best reading experience, we recommend reading via [GitBook](https://www.gitbook.com/book/geemus/http-api-design/details).
+For the best reading experience, we recommend reading via [GitBook](https://www.gitbook.com/read/book/geemus/http-api-design).
 
 ### Gitbook Translations
  * [English](https://geemus.gitbooks.io/http-api-design/content/en/index.html)