Merge branch 'development'
adding an explicit phpunit configuration and not just a bootstrap
Merge branch 'master' into development
adding build directory to ignore list
refactoring AppConfig to get rid of some duplication
adding stub, test and updated implementation for BaseConfig
adding test and implementation for unsetting from mutable config
adding some more tests for unsetting values, iterating and checking existence of module parameters
adding code to ensure we check for existence of a parameter in the appropriate module
adding some ideas for features to easily work with different configurations
adding notice about Roadmap and fixing some errata