Automatic ensembling of databases

[Aske-Rosted]

Automatic ensembling of databases when loading from config
For some use cases having several separate databases rather than one large db is preferable. However our current load from config only allows for a single database.

The feature should allow for the path entry in the config files to be either a path or a list of path. In the case where the path is a list of path the databases should be merged. Any potential selections should be applied to all of the databases.