Add a command to list all running process

[robsonpeixoto]

How to get the status of all running process? For example, docker-compose ps is very useful to get the process state.

% docker-compose ps
            Name                          Command              State                    Ports                  
---------------------------------------------------------------------------------------------------------------
risk-assessments_kafka_1       /etc/confluent/docker/run       Up      0.0.0.0:9092->9092/tcp,:::9092->9092/tcp
risk-assessments_postgres_1    docker-entrypoint.sh postgres   Up      0.0.0.0:5432->5432/tcp,:::5432->5432/tcp
risk-assessments_zookeeper_1   /etc/confluent/docker/run       Up      2181/tcp, 2888/tcp, 3888/tcp            

[DarthSim]

Hey! It looks like a duplicate for #108