feat: execute service as distributed erlang (#96)

To create a cluster with distributed nodes, the following changes were made:

* Use [`dns_cluster`][0] to execute distributed nodes
* Add _script_ to execute distributed nodes locally

Also, improve local execution by:

* Use [`mix release`][1] to make easier [deploy `phoenix`][2]
* Use [`compose watch`][3] to synchronize code from the host with the service

Some minor improvements:

* Ignore files and folders in git and docker
* Remove boilerplate comments

[0]: https://github.com/phoenixframework/dns_cluster
[1]: https://hexdocs.pm/mix/Mix.Tasks.Release.html
[2]: https://hexdocs.pm/phoenix/releases.html
[3]: https://docs.docker.com/compose/how-tos/file-watch/

Co-authored-by: Joao P Dubas <joao.dubas@gmail.com>
Reviewed-on: #96
Co-authored-by: Joao P Dubas <joao.dubas+gitea@gmail.com>
Co-committed-by: Joao P Dubas <joao.dubas+gitea@gmail.com>

config/config.exs

@@ -1,10 +1,3 @@
-# This file is responsible for configuring your application
-# and its dependencies with the aid of the Mix.Config module.
-#
-# This configuration file is loaded before any dependency and
-# is restricted to this project.
-
-# General application configuration
 import Config
 
 config :wabanex,
@@ -21,7 +14,6 @@ config :wabanex, Wabanex.PromEx,
   grafana: :disabled,
   metrics_server: :disabled
 
-# Configures the endpoint
 config :wabanex, WabanexWeb.Endpoint,
   url: [host: "localhost"],
   secret_key_base: "wkyuhU+mCGwXUSBYVKZSRGoFmDYCbOFzdokbVmBBI9JgCWOqGPfuA/3JI5/b4Wdl",
@@ -29,14 +21,10 @@ config :wabanex, WabanexWeb.Endpoint,
   pubsub_server: Wabanex.PubSub,
   live_view: [signing_salt: "SXtw7DzV"]
 
-# Configures Elixir's Logger
 config :logger, :console,
   format: "$time $metadata[$level] $message\n",
   metadata: [:request_id]
 
-# Use Jason for JSON parsing in Phoenix
 config :phoenix, :json_library, Jason
 
-# Import environment specific config. This must remain at the bottom
-# of this file so it overrides the configuration defined above.
 import_config "#{config_env()}.exs"