Docker image improvements

[Tedezed]

:v: What does this PR do?.

Improve Docker image, easy boot

:mag: How should this be manually tested?

cp .env.example .env
cp config/database.yml.example config/database.yml
docker-compose up

Before this PR

Non-functional docker image, wrong versions.

After this PR

Functional Docker image with a supervisord boot system, version update.

:shipit: Does this PR changes any configuration file?

• [x] new environment variable in .env.example?

By @juanjoselopezroldan and @Tedezed, @Guadaltech

[Tedezed]

For our part we have already finished all the improvements