Merge pull request #1319 from meonkeys/patch-1

README: link to canonical Phoenix Server doc

Author: PromoFaux

README.md

@@ -254,7 +254,7 @@ Do not attempt to upgrade (`pihole -up`) or reconfigure (`pihole -r`).  New imag
     * If you care about your data (logs/customizations), make sure you have it volume-mapped or it will be deleted in this step.
 3. Start your container with the newer base image: `docker run <args> pihole/pihole` (`<args>` being your preferred run volumes and env vars)
 
-Why is this style of upgrading good?  A couple reasons: Everyone is starting from the same base image which has been tested to known it works.  No worrying about upgrading from A to B, B to C, or A to C is required when rolling out updates, it reduces complexity, and simply allows a 'fresh start' every time while preserving customizations with volumes.  Basically I'm encouraging [phoenix server](https://www.google.com/?q=phoenix+servers) principles for your containers.
+Why is this style of upgrading good?  A couple reasons: Everyone is starting from the same base image which has been tested to known it works.  No worrying about upgrading from A to B, B to C, or A to C is required when rolling out updates, it reduces complexity, and simply allows a 'fresh start' every time while preserving customizations with volumes.  Basically I'm encouraging [phoenix server](https://martinfowler.com/bliki/PhoenixServer.html) principles for your containers.
 
 To reconfigure Pi-hole you'll either need to use an existing container environment variables or if there is no a variable for what you need, use the web UI or CLI commands.