Reduce amount of packages

[pago]

Explain the problem

We originally split Melody into lots of packages. While technically pretty it is questionable whether it actually delivered anything apart of complexity.

As part of this proposal, we'd reduce the amount of packages down to a more manageable size.

The Goal

Our users should be able to install and update Melody with at most 3 packages:

• The loader for their build system (Webpack / Rollup)
• The runtime (melody-idom, Preact, React, Inferno)
• The component system (melody-component, melody-hooks)

Details would still need to be discussed.