PackageModel Library

This library defines the model objects for describing Packages.

The intent of this library is that these should be pure model objects and contain a complete specification of a single local package. The convention system is encoded in the model via the PackageLoading library, and then the individual packages are combined into a cohesive PackageGraph for the high-level operations.

NOTE: This library contains types which shadows definitions from the PackageDescription library, but they are fundamentally different -- those model objects describe the model of the package manifest itself, not the overall package.