asciinema: add option placeholders

pages/common/asciinema.md

@@ -6,28 +6,28 @@
 
 - Associate the local install of `asciinema` with an asciinema.org account:
 
-`asciinema auth`
+`asciinema {{[a|auth]}}`
 
 - Make a new recording and save it to a local file (finish it with `<Ctrl d>` or type `exit`):
 
-`asciinema rec {{path/to/recording.cast}}`
+`asciinema {{[r|record]}} {{path/to/recording.cast}}`
 
 - Replay a terminal recording from a local file:
 
-`asciinema play {{path/to/recording.cast}}`
+`asciinema {{[p|play]}} {{path/to/recording.cast}}`
 
 - Replay a terminal recording hosted on <https://asciinema.org>:
 
-`asciinema play https://asciinema.org/a/{{cast_id}}`
+`asciinema {{[p|play]}} https://asciinema.org/a/{{cast_id}}`
 
 - Make a new recording, limiting any idle time to at most 2.5 seconds:
 
-`asciinema rec {{[-i|--idle-time-limit]}} 2.5`
+`asciinema {{[r|record]}} {{[-i|--idle-time-limit]}} 2.5`
 
 - Print the full output of a locally saved recording:
 
-`asciinema cat {{path/to/recording.cast}}`
+`asciinema {{[ca|cat]}} {{path/to/recording.cast}}`
 
 - Upload a locally saved terminal session to asciinema.org:
 
-`asciinema upload {{path/to/recording.cast}}`
+`asciinema {{[u|upload]}} {{path/to/recording.cast}}`