Keep deployment intelligence in `deployment.yml`

[edro15]

Modify deploy.py to make sure private apps are repackaged with proper configuration files depending on instructions provided by deployment.yml. In particular, edits are required here:

Splunk-Apps-Deployment-Architecture/deploy.py

Line 48 in af939ef

path = check_all_letter_cases(sys.argv[1], app)

Requested flow:

• Read config key for each private apps specified in deployment.yml
• If the value is not empty
  • Add / Merge configuration files specified at the read paths to the downloaded app
  • Repackage the app

config accepted values are either a list of paths (see environments/uat/ses/deployment.yml as example) or nothing (e.g. config: [])

This is important to keep the "intelligence" of the deployments in deployment.yml. In this way changes and integrations should be easier and more modular. As a consequence, the integration of other kind of configuration in the app could be potentially done with less coding, reducing the complexity of touching running functions, but just adding a new one.

[bdebek-splunk]

Issue resolved in #69