SPEC: Add a new key in the root of the config file for services

[xmnlab]

Add a new key in the root of the config file for services. Example:

version: 1.0.0
compose-app: docker-compose
env-file: .env
services:
  default: service1,service3
  list:
    - name: service1
      health-check: true
    - name: service2
      health-check: false
    - name: service3
      health-check: true

when the services item is given, groups should not be given, otherwise it should raise an error.

[xmnlab]

example for a call:

containers-sugar start

[xmnlab]

example of an error message for a spec conflict for groups and services:

`services` and `groups` flag given. Just use one of them is allowed.

[joel5vega]

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Hi @xmnlab , I am trying to use this logic, is it ok?

[xmnlab]

not sure ... it is not really clear what it is doing

[xmnlab]

fixed by #110 . thanks @joel5vega