A way to hide posts for Steem Apps in the metadata

Proposal

In the json_metadata object, a property called hide can be implemented which expects an array of strings which represent the app names the posts shouldn't be visible for.

Mockups / Examples

Example for not showing content on steemit and busy:
json_metadata:{...,hide: ['steemit', 'busy']}

Let's say I'm using DTube and I no longer want the video to be showing.
json_metadata:{...,hide: ['dtube']}

Benefits

With many Steem apps, a user's Steemit feed can be filled with content from different apps and sometimes they don't want it to show on their Steemit feed.