Refactor multiple value keys registration with ConfigurationActionImpl classes

• Type: Technical Task
• Status: Closed
• Resolution: Won't Fix
• Affects Version/s: None
• Fix Version/s: 7.0.0 M3
• Component/s: Portal Services, Portal Services > Configuration Management, Portal Services > Configuration Management > Portlets
• Labels: None
• Git Pull Request: https://github.com/jorgeferrer/liferay-portal/pull/380

In the spirit of LPS-47528, provide some more intuitive and not error prone way to register multiple value keys of high level settings with their configuration actions.

Right now it is done with a static variable that must be used in the ConfigurationActionImpl constructor.