Add release notes for v1.3.1

CHANGELOG.md

 # Release Notes
 
+## Version 1.3.1 - 2019-08-13
+
+* Update code references to point to new documentation site [#5052](https://github.com/kubernetes/minikube/pull/5052)
+* Localization support for help text [#4814](https://github.com/kubernetes/minikube/pull/4814)
+* Upgrade cheggaaa/pb from v1.0.27 to v3.0.1 [#5025](https://github.com/kubernetes/minikube/pull/5025)
+* Restore --disable-driver-mounts flag [#5026](https://github.com/kubernetes/minikube/pull/5026)
+* Fixed the template for dashboard output [#5004](https://github.com/kubernetes/minikube/pull/5004)
+* Use a temp dest to atomically download the iso [#5000](https://github.com/kubernetes/minikube/pull/5000)
+
+Thank you to our merry band of contributors for assembling this last minute bug fix release.
+
+- Jituri, Pranav
+- Medya Ghazizadeh
+- Pranav Jituri
+- Ramiro Berrelleza
+- Sharif Elgamal
+- Thomas Strömberg
+- josedonizetti
+
 ## Version 1.3.0 - 2019-08-05
 
 * Added a new command: profile list [#4811](https://github.com/kubernetes/minikube/pull/4811)