Simple config updating in `AppInitialized`
Simple config updating in `AppInitialized`

Subclasses of `AppInitialized` now can easily pass an additional
configuration dict to `AppInitialized.create_app`.

agdsn/sipa,MarauderXtreme/sipa,agdsn/sipa,MarauderXtreme/sipa,lukasjuhrich/sipa,lukasjuhrich/sipa,lukasjuhrich/sipa,MarauderXtreme/sipa,agdsn/sipa,lukasjuhrich/sipa,agdsn/sipa