Add docker environment

[Kolyunya]

This should make the development of the library much much easier.

There will be no need to install any services locally.

This can also potentially simplify the CI configuration.

Only PostgreSQL is currently supported in this proof of concept version.

[BenMorel]

Hi, thanks for your PR. I'm trying it out but getting an error:

$ docker-compose up --detach

ERROR: The Compose file './docker-compose.yml' is invalid because:
networks.network value Additional properties are not allowed ('name' was unexpected)
volumes.postgres value Additional properties are not allowed ('name' was unexpected)

Any idea what's wrong? I'm using docker 19.03.6 and docker-compose 1.25.5.

[Kolyunya]

@BenMorel well, this obviously has to do with the docker-compose version. We probably should try to support as many of old versions as we could. So I'm going to check how we can refactor the config without using name properties.

[Kolyunya]

@BenMorel can you try the new config version? I've removed name properties altogether.