Note about Python 3 kernel

minimal-kernel/README.md

 # Kernel Gateway Stack
 
 ## What it Gives You
+
 * [Jupyter Kernel Gateway](https://github.com/jupyter-incubator/kernel_gateway) that enables programmatic access to kernels
+* Python 3 kernel
 * No preinstalled scientific computing packages
 * [tini](https://github.com/krallin/tini) as the container entrypoint
 
@@ -15,4 +17,4 @@ docker run -d -p 8888:8888 jupyter/minimal-kernel
 
 ## Docker Options and More Information
 * For more information on the Kernel Gateway and its configuration options see the
-[Kernel Gateway Repository](https://github.com/jupyter-incubator/kernel_gateway#what-it-gives-you).
\ No newline at end of file
+[Kernel Gateway Repository](https://github.com/jupyter-incubator/kernel_gateway#what-it-gives-you).