Add support for including outputs from other project types

[davidfowl]

The idea behind this feature is to make other things (csproj, assemblies) visible to vNext via project.json. Today, project.json can only reference other things that have a project.json or nuget packages. This doesn't change that but it allows other project types to be seen as a project.json based project without opting into the new compilation model.

Scenarios

1. Using a csproj as a project reference
2. Packing output from other project types (csproj) into a single nupkg

{
  "frameworks": {
    "net45": {
      "dependencies": {
        "Newtonsoft.Json": "5.0.8"
      }
    },
    "win8": {
      "bin": {
        "assembly": "../ClassLibrary3.WindowsStore8/bin/{configuration}/ClassLibrary3.dll",
        "pdb": "../ClassLibrary3.WindowsStore8/bin/{configuration}/ClassLibrary3.pdb"
      }
    },
    "k10": {
      "dependencies": {
        "Newtonsoft.Json": "5.0.8"
      }
    }
  }
}

In the above example. We're building a single vnext class library with multiple outputs. The windows8 target framework will not be compiled but will instead use the pdb and dll specified for building the nuget package (kpm build)

[borgdylan]

Would it be possible to support any buildable msbuild project instead of only csproj?

[davidfowl]

I never finished writing up this feature but it's not tied to msbuild. I was just listing scenarios.

In fact we're not going to call msbuild at all but you'll be able to pick up outputs from those projects.