Create a Phoenix Bell App

[uri]

It would be cool to make a simple Phoenix application as a talk.

• Create a new "bell" /bells/new
  • Pick a name: elixir-ottawa
  • redirect to /door/elixir-ottawa
• Display nothing
• ...
• Client goes to /bell/elixir-ottawa
• People viewing /door/elixir-ottawa see a flashing screen
• /door/elixir-ottawa gets snoozed
• More people go to /bell/elixir-ottawa
• /door/elixir-ottawa starts flashing again

This will be useful for people change peoples' lives, like @sseg who are on door duty for meetups.

This app can show off sockets and even GenServers for debouncing back to back rings.

[maxneuvians]

And it could use graphql subscriptions!!! ;) I like it, might do it for November?