Value Providers for CONGA

currently CONGA supports only parameter values from it's own environment files, or from default values from role definitions.

we need a support for "value providers", which can provide config parameter values from external (pluggable) sources, e.g.:

• command line (java system parameter)

• e.g. host name/ip addresses from ansible inventory

• e.g. password from ansible vault

the provider should support single values or list of values, mapped to a "configuration parameter key" like xx.yy.param1.

the external values could be references in the environment using a syntax like: