TreePropValuePair

Defines a single tree prop override. Unlike ClassValuePair there can be multiple TreePropValuePair with the same corresponding class.

TreeProp's should be declared separately and then overridden in TreePropProvider. If there are no overrides available, then the default value will be used (if any).

You can create a Pair with the to infix function, e.g. StringTreeProp to "Hello World!".