Revive the Self-hosted Broadcast System

[hubertdeng123]

Primary Goal

Provide an easier way to announce changes to current users of self-hosted Sentry. Potentially also ease the pipeline of providing feedback to us

There appears to be existing infrastructure for a broadcast system in SaaS. However, our implementation needs to be a bit different because it requires us to somehow stay connected to all the other self hosted instances out in the wild.

Implementation

We can do this by scheduling a task to be run on self-hosted instances periodically. It can pick up any new broadcasts that are available upstream to display.

Tasklist

• [ ] Create endpoint in getsentry to get all self-hosted broadcasts
• [ ] Create interface in self-hosted to show broadcasts that come in upstream
• [ ] Create task in sentry for self-hosted instances to periodically get broadcasts upstream from sentry.io

[chadwhitacre]

I think we rewrite this as, "Send a broadcast." Wdyt @azaslavsky?