Dynamic Avrora private clients

[Strech]

It would be cool to have interface where we could stay compile-time for core modules, but start them dynamically with a supervision.

By default we start under :default or :avrora key more dynamic avrora clients could be added with their own configurations.

The interface should allow calls like

Avrora.decode("...")
Avrora.decode(pid(), "...")

defmodule MyClient do
  use Avrora.DymanicClient, name: :my_client
end

MyClient.decode("...")
# or
Avrora.decode(:my_client, "...")

Maybe we can leverage Elixir's Registry + DynamicSuperviser