doc(deploying-apps.md): fix broken link for k8s revisions (#394)

Fixes deis/workflow#393

Author: arschles

src/applications/deploying-apps.md

@@ -64,7 +64,7 @@ DEIS_DEPLOY_BATCHES                             | the number of pods to bring up
 DEIS_DEPLOY_TIMEOUT                             | deploy timeout in seconds - there are 2 deploy methods, current (RC) and Deployments (see below) and this setting affects those a bit differently (default: 120)
 DEIS_KUBERNETES_DEPLOYMENTS                     | if enabled [Deployments][] is used to handle an application deploy instead of [ReplicationControllers][]
                                                 | any value is acceptable to turn on [Deployments][], to turn it off either remove or pass an empty string (default: off)
-KUBERNETES_DEPLOYMENTS_REVISION_HISTORY_LIMIT   | how many [revisions][[kubernetes-deployment-revision]] Kubernetes keeps around of a given Deployment (default: all revisions)
+KUBERNETES_DEPLOYMENTS_REVISION_HISTORY_LIMIT   | how many [revisions][kubernetes-deployment-revision] Kubernetes keeps around of a given Deployment (default: all revisions)
 
 ### Deploy Timeout