Pros and cons of one-or-many-package publishing of design system components

[JedWatson]

There are pretty significant downstream implications of how design systems are published - whether they're a single package for all components (e.g Material UI), a package for each component (e.g Atlaskit) or a few packages for groups of components (e.g Blueprint)

We should document the pros and cons we've learned of each, and how this relates to release cadence as well (#13). This is probably not a one-size-fits-all thing across design systems.