Refining scope

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The Scope section in the design vignette starts with:

The {epiparameter} R package is a library of epidemiological parameters, and provides a class (i.e. data structure) and helper functions for working with epidemiological parameters and distributions.

This has three components:

1. Library of epiparameters
2. Class/data structure for epidemiological parameters
3. Helper functions for working with epidemiological parameters and distributions

Could we expand on this to be clearer on what falls within and outside of the scope for these three components?