added an abstract factory for configs
added call to attachDefaultListeners if method has been defined
added abstract factory test
wrong key ...
added some more functionality
fixed assertion and empty line at file ending
fix more assertions and more file endings ...
fix assertion
fix data provider
fix data provider
incorporated feedback from @weierophinney
removed instantiation of Zend\Config\Config, adjusted test
replaced @return $this with @return self
Merge pull request #4860 from sarge-ch/abstract-config-factory

abstract factory for configs reading keys from merged config
Merge branch 'feature/4860' into develop

Close #4860