Missing library support

[turboMaCk]

There are leftover bits for library support like doc compilation however library compilation is not working because of:

1. parseElmJsonDeps is not compatible. Libraries don't have direct and indirect deps - easy fix
2. libraries must have version ranges in dependencies

The biggest problem to support this is version ranges. Highest possible might not exit and the lowest one might not be most recent resolving in elm make downloading newer versions of packages (I expect this would fail within sandbox).

I believe this was discussed: #14
and also: https://discourse.elm-lang.org/t/resolving-dependencies-in-elm-0-19-package-projects/2589

This situation has a workaround though one can specify lib deps with most current most recent version as instance "elm/core": "1.0.2 <= v < 2.0.0".