Implement the `DataManager`
The DataManager should be a BaseDataGroup-derived class that is meant to represent the root of a data tree.
It should have the following features:
- Be coupled to a specific data directory
- Load in the data, creating the data tree
- For loading, use a YAML configuration file
- Supply the base functions for loading
- Be extendable via Mixin classes
Edited by Utopia Developers