Use printf, not echo when creating secrets
Update the docs so that users don't use `echo` when creating
secrets from STDIN. `echo` adds a trailing new line, so users
will probably be confused when their passwords don't work.
@@ -36,7 +36,7 @@ For detailed information about using secrets, refer to [manage sensitive data wi
### Create a secret
```bash
-$ echo <secret> | docker secret create my_secret -
+$ printf <secret> | docker secret create my_secret -
onakdyv307se2tl7nl20anokv
