Fix docker-machine mount reference page (docker#5142)

* Fix reference page for `docker-machine mount`

Signed-off-by: Harald Albers <[email protected]>

* Add reference page for `docker-machine mount` to navigation

Signed-off-by: Harald Albers <[email protected]>

Author: albers

Diff for: _data/toc.yaml

@@ -2784,6 +2784,8 @@ manuals:
       title: kill
     - path: /machine/reference/ls/
       title: ls
+    - path: /machine/reference/mount/
+      title: mount
     - path: /machine/reference/provision/
       title: provision
     - path: /machine/reference/regenerate-certs/

Diff for: machine/reference/index.md

@@ -13,6 +13,7 @@ title: Docker Machine command-line reference
 -   [ip](ip.md)
 -   [kill](kill.md)
 -   [ls](ls.md)
+-   [mount](mount.md)
 -   [provision](provision.md)
 -   [regenerate-certs](regenerate-certs.md)
 -   [restart](restart.md)

Diff for: machine/reference/mount.md

@@ -26,9 +26,10 @@ Now you can use the directory on the machine, for mounting into containers.
 Any changes done in the local directory, will be reflected in the machine too.
 
 ```none
+$ eval $(docker-machine env dev)
 $ docker run -v /home/docker/foo:/tmp/foo busybox ls /tmp/foo
 bar
-$ docker touch foo/baz
+$ touch foo/baz
 $ docker run -v /home/docker/foo:/tmp/foo busybox ls /tmp/foo
 bar
 baz