Text Chat Retention Expiration

I think a feature to remove messages sent (any and in all channels, private and public) would be a good idea. Some information shared on discord can be potentially volatile like birthdays, emails, any passwords etc. 

A retention period would be beneficial in that old messages would no longer be available after whatever period you choose to uphold. This would work something like text messages on iphone where a user can choose to delete all text after a year, 6 months, etc.