Improved OFBiz configuration management for containers

It's hard to use OFBiz with containers and other deployment scenarios because the OFBiz configuration is intertwined with source files and there are a lot of them.

We also need:

• the ability to override configuration properties
• load configs from a single / handful of files in a single location
• optionally load from multiple sources (files, db, configuration services like kubernetes, consul ,etc) .