Add a command to allow mods to turn off/on alerts for mods/broadcaster

[cmjchrisjones]

Is your feature request related to a problem? Please describe. As has become apparent, there have been a lot of follow bot attempts in recent times. This issue is to discuss the feasability of adding a chat command which would suspend or enable showing the overlays.

Describe the solution you'd like Something like submitting !overlaysoff of safemode on/safemode off, which would hold internally a boolean property that if false, would not continue processing the sending of events to display or play the alert/associated sound effects. In the case of being bot attacked, this would take the pressure of the streamer turning overlays on/off in OBS and giving moderators the ability to do that, as they will potentially also be the ones setting the channel into slow/follower only modes