The new cpp-lib template should default to loading "hybrid" paper/fabric props/targets

[jonthysell]

Summary

Right now old libs load uwp lib props/targets, and new libs load composition lib props/targets. We should instead have an entry point that conditionally loads one of the other depending on if the lib is currently being built for paper or fabric

Motivation

There will only be one lib template going forward and it must support paper and fabric.

Basic Example

No response

Open Questions

No response