Update to bring back mention of container links compatibility

Author: yashodhanmohan

content/en/docs/concepts/services-networking/service.md

@@ -450,9 +450,7 @@ variables and DNS.
 ### Environment variables
 
 When a Pod is run on a Node, the kubelet adds a set of environment variables
-for each active Service.  It supports both granular variables like `{SVCNAME}_PORT_{SVCPORT}_PROTO` and more (see [makeLinkVariables](https://github.com/kubernetes/kubernetes/blob/dd2d12f6dc0e654c15d5db57a5f9f6ba61192726/pkg/kubelet/envvars/envvars.go#L72))
-as well as simpler `{SVCNAME}_SERVICE_HOST` and `{SVCNAME}_SERVICE_PORT` variables,
-where the Service name is upper-cased and dashes are converted to underscores.
+for each active Service. It adds `{SVCNAME}_SERVICE_HOST` and `{SVCNAME}_SERVICE_PORT` variables, where the Service name is upper-cased and dashes are converted to underscores. It also supports variables (see [makeLinkVariables](https://github.com/kubernetes/kubernetes/blob/dd2d12f6dc0e654c15d5db57a5f9f6ba61192726/pkg/kubelet/envvars/envvars.go#L72)) that are compatible with Docker Engine's "_[legacy container links](https://docs.docker.com/network/links/)_" feature.
 
 For example, the Service `redis-master` which exposes TCP port 6379 and has been
 allocated cluster IP address 10.0.0.11, produces the following environment