Change configuration and docker compose

Signed-off-by: Thomas Citharel <tcit@tcit.fr>

Dockerfile

@@ -1,4 +1,4 @@
-FROM elixir:1.6
+FROM elixir:1.7
 
 RUN apt-get update && apt-get install -y build-essential inotify-tools postgresql-client
 
@@ -8,4 +8,4 @@ COPY docker/entrypoint.sh /bin/entrypoint
 
 WORKDIR /app
 
-EXPOSE 4000
+EXPOSE 4000 4001 4002