On-live notification system

[Fenrirthviti]

Implement system for notification that includes:

• Email notifications when channels go live
• Option to opt-in on all channels, or pick channels manually
• This will likely be a new database entry for each channel. When someone subscribes, it will add their account to a list of notifications to be called through on_publish somehow
• Find a way of preventing email spam if someone connects/disconnects rapidly. Only send one email every 5 min or so.

[Fenrirthviti]

Proof of concept complete, need to implement user subscribe functionality. Currently works by manually editing database.

[Fenrirthviti]

Bulk of the work complete, on-live notices working, and users can sub to any channel they want either through the API or through a subscribe button on the stream player page.

[Fenrirthviti]

Cleaned up several functions and make subscription list API function work better.