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/dev.exs

@@ -1,17 +1,14 @@
 import Config
 
-# Configure your database
+config :wabanex,
+  dns_cluster_query: :ignore,
+  dns_cluster_resolver: Wabanex.DevDNSClusterResolver
+
 config :wabanex, Wabanex.Repo,
   database: "wabanex_dev",
   show_sensitive_data_on_connection_error: true,
   pool_size: 10
 
-# For development, we disable any cache and enable
-# debugging and code reloading.
-#
-# The watchers configuration can be used to run external
-# watchers to your application. For example, we use it
-# with webpack to recompile .js and .css sources.
 config :wabanex, WabanexWeb.Endpoint,
   http: [port: 4000],
   debug_errors: true,
@@ -19,36 +16,8 @@ config :wabanex, WabanexWeb.Endpoint,
   check_origin: false,
   watchers: []
 
-# ## SSL Support
-#
-# In order to use HTTPS in development, a self-signed
-# certificate can be generated by running the following
-# Mix task:
-#
-#     mix phx.gen.cert
-#
-# Note that this task requires Erlang/OTP 20 or later.
-# Run `mix help phx.gen.cert` for more information.
-#
-# The `http:` config above can be replaced with:
-#
-#     https: [
-#       port: 4001,
-#       cipher_suite: :strong,
-#       keyfile: "priv/cert/selfsigned_key.pem",
-#       certfile: "priv/cert/selfsigned.pem"
-#     ],
-#
-# If desired, both `http:` and `https:` keys can be
-# configured to run both http and https servers on
-# different ports.
-
-# Do not include metadata nor timestamps in development logs
 config :logger, :console, format: "[$level] $message\n"
 
-# Set a higher stacktrace during development. Avoid configuring such
-# in production as building large stacktraces may be expensive.
 config :phoenix, :stacktrace_depth, 20
 
-# Initialize plugs at runtime for faster development compilation
 config :phoenix, :plug_init_mode, :runtime