Add starring functionality to Messages #354
Description
Why don't Messages have stars?
I want to be able to build apps that allow users to star/like/whatever a message in a channel. By supporting this, you'll enable apps to have the starring functionality without requiring that posts (or messages) are posted to the public feed. Currently, apps like Sprinter can post to both a channel and the global Post stream, and when reading from the channel, can use annotations on Messages to find the associated Posts, and use their star count. But if I want my Messages to exist only in the Channel (and not exist in the global stream), I have to build my own backend and keep track of stars, etc.
I think there are a lot of cool app ideas that don't involve traditional microblogging, and by not supporting stars (and maybe reposts – but I feel this is less important) on Messages, it's harder for devs to build apps that take advantage of your architecture without requiring the microblogging aspect (as Sprinter does – to glue the starring/reposting features on).