Support docker-compose artifact in Nulecule spec

[rtnpro]

Problem statement

Docker compose is, in many ways, analogous to a Nulecule file. Services in Docker compose YAML file is analogous to items in the graph in a Nulecule file. So, we don't need a separate compose artifact for each item in graph, but just one, for the user facing application (e.g., sentry, etherpad, wordpress).

Possible solutions

• Allow items in graph have no artifact for a provider [Easyfix]
• Incorporate more information in Nulecule file about application architecture and generate provider artifacts automatically.

[goern]

Could you elaborate on this a little more?