Point init containers to documentation

The proposal doesn't reflect reality.

docs/user-guide/petset/bootstrapping/index.md

@@ -8,7 +8,7 @@
 
 This purpose of this guide is to help you become familiar with the runtime initialization of [Pet Sets](/docs/user-guide/petset). This guide assumes the same prerequisites, and uses the same terminology as the [Pet Set user document](/docs/user-guide/petset).
 
-The most common way to initialize the runtime in a containerized environment, is through a custom [entrypoint](https://docs.docker.com/engine/reference/builder/#entrypoint). While this is not necessarily bad, making your application pid 1, and treating containers as processes in general is good for a few reasons outside the scope of this document. Doing so allows you to run docker images from third-party vendors without modification. We will not be writing custom entrypoints for this example, but using a feature called [init containers](http://releases.k8s.io/{{page.githubbranch}}/docs/proposals/container-init.md), to explain 2 common patterns that come up deploying Pet Sets.
+The most common way to initialize the runtime in a containerized environment, is through a custom [entrypoint](https://docs.docker.com/engine/reference/builder/#entrypoint). While this is not necessarily bad, making your application pid 1, and treating containers as processes in general is good for a few reasons outside the scope of this document. Doing so allows you to run docker images from third-party vendors without modification. We will not be writing custom entrypoints for this example, but using a feature called [init containers](http://kubernetes.io/docs/user-guide/production-pods/#handling-initialization), to explain 2 common patterns that come up deploying Pet Sets.
 
 1. Transferring state across Pet restart, so that a future Pet is initialized with the computations of its past incarnation
 2. Initializing the runtime environment of a Pet based on existing conditions, like a list of currently healthy peers