Develop future S3 class structure

[emhart]

Develop a strategy for summarizing, visualizing and writing model output. Currently the project has no roadmap to create a standardized output. Consider all desired model outputs and how best to organize them as classes. Would be helpful to get a list from someone else in the group.

[emhart]

S3 classes implemented, but further thought needs to go into other potential classes.

[emhart]

This is now done with a generalize null model structure and then unique classes for each type.