Implement notifications #128
Description
When a new idea is created or edited, we need some notification to go out.
I think as an initial implementation we need to at least notify admins about new ideas.
Ideally we should have some sort of moderation and when an idea is approved, we could have a notification to all users that subscribed to ideas notifications. Maybe we could hook into some sort of reputation system to limit the amount of moderation based on the user historical activity or something.