Updates on cli reference documentation

- Update ps with `--last` flag
- Update commands with current output
- Make sure hugo does not detect the wrong language
- Update usage for `tag` command to be more coherent with the other ones

Signed-off-by: Vincent Demeester <vincent@sbr.pm>

docs/reference/commandline/logout.md

@@ -10,12 +10,15 @@ parent = "smn_cli"
 
 # logout
 
-    Usage: docker logout [SERVER]
+```markdown
+Usage:  docker logout [SERVER]
 
-    Log out from a Docker registry, if no server is
-	specified "https://index.docker.io/v1/" is the default.
+Log out from a Docker registry.
+If no server is specified, the default is defined by the daemon.
 
-      --help          Print usage
+Options:
+      --help   Print usage
+```
 
 For example: