update current version of readme

readme.md

@@ -18,8 +18,7 @@ It also contains information on keeping your instance of CryptPad up to date.
 
 ## Current version
 
-CryptPad v1.15.0 (Poukai) released the 12th September 2017
-See [Cryptad-Releases](docs/releases)
+The most recent version and all past release notes can be found [here](https://github.com/xwiki-labs/cryptpad/releases/).
 
 ## Setup using Docker