Formatting changes to make 1.12.x ref docs buildable in Jekyll

Signed-off-by: Misty Stanley-Jones <misty@docker.com>

docs/reference/commandline/attach.md

@@ -1,14 +1,11 @@
-<!--[metadata]>
-+++
-title = "attach"
-description = "The attach command description and usage"
-keywords = ["attach, running, container"]
-[menu.main]
-parent = "smn_cli"
-+++
-<![end-metadata]-->
-
-# attach
+---
+redirect_from:
+  - /reference/commandline/attach/
+description: The attach command description and usage
+keywords:
+- attach, running, container
+title: docker attach
+---
 
 ```markdown
 Usage: docker attach [OPTIONS] CONTAINER
@@ -42,13 +39,13 @@ the container. You can detach from a container and leave it running using the
 It is forbidden to redirect the standard input of a `docker attach` command
 while attaching to a tty-enabled container (i.e.: launched with `-t`).
 
-While a client is connected to container's stdio using `docker attach`, Docker 
-uses a ~1MB memory buffer to maximize the throughput of the application. If 
-this buffer is filled, the speed of the API connection will start to have an 
-effect on the process output writing speed. This is similar to other 
-applications like SSH. Because of this, it is not recommended to run 
-performance critical applications that generate a lot of output in the 
-foreground over a slow client connection. Instead, users should use the 
+While a client is connected to container's stdio using `docker attach`, Docker
+uses a ~1MB memory buffer to maximize the throughput of the application. If
+this buffer is filled, the speed of the API connection will start to have an
+effect on the process output writing speed. This is similar to other
+applications like SSH. Because of this, it is not recommended to run
+performance critical applications that generate a lot of output in the
+foreground over a slow client connection. Instead, users should use the
 `docker logs` command to get access to the logs.