Self destruct, auto delete messages

[gitbq]

Is there any chance of adding more deleting features to siskin?

1. Globally delete all messages after certain time.
   This functionality is available in android clients like "conversations" and also the Monal client.

2. Option to set specific time per chat.
   Monal currently supports 3 day option on a per chat basis.

3. Option to clear all messages in a chat on demand.
   Snikket ios app forked from Siskin supports this feature.

No doubt messages may not be deleted in all places. But having the ability to clear my local messages, and knowing that recipients who are not tech savvy will also have their messages delete after a certain time is helpful.

Thanks again.