Add the heroku --remote switch

This remote selects the app based on your current repo remotes
For example heroku logs --remote staging
More info at https://devcenter.heroku.com/articles/using-the-cli

plugins/heroku/_heroku

@@ -154,5 +154,6 @@ case "$words[1]" in
 _arguments \
   $_command_args \
   '(--app)--app[the app name]' \
+  '(--remote)--remote[the remote name]' \
   &&  return 0