Modularise docker-compose.

A bit of background: In my team we have people working on different sections of a multi service application. We don't all need to run everyone else's services. Also we have multiple swarm environments. The UAT environment runs all services but we have 2 productions swarms running different types of services.

The issue was, having one docker-compose file was progressively harder and harder to maintain, even taking into account all the file overwriting, aliases and other devices provided by yaml/docker-compose.

The solution is: modules (for us anyway)

I've been using this script for a while and I'm confident it helps us in managing all our environments very efficiently so I thought I'd make it available open source. The script was heavily engrained in our environments, I had to rewrite quite a few things to make it open source. I will be using this version in our infrastructure and hopefully will iron out all the bugs.

• A service is a folder with a docker-compose.yml and docker-compose.{environment}.yml files to go along with it.
• A group is a collection of services working together.
• An environment is a target configuration for all services
• decompose will generate a docker-compose.yml file specific to a list of services for a given environment
• if a .env.{environment} file is available at the root, it will be used by decompose.py

Just download the decompose.py and create your decompose.conf.json. Then use it as a standard script as described in the tests/ folder.