Support (Conditional) Framework Assembly References

[bartelink]

This is a split of an original issue #68 which, after some analysis breaks out into more than one problem.

I'm using latest of Microsoft.AspNet.WebApi which (indirectly) pulls in Microsoft.Net.Http. It's .nuspec has:

  <frameworkAssemblies>
      <frameworkAssembly assemblyName="System.Net.Http" targetFramework=".NETFramework4.5" />
      <frameworkAssembly assemblyName="System.Net.Http.WebRequest" targetFramework=".NETFramework4.5" />
      <frameworkAssembly assemblyName="System.Net.Http" targetFramework="MonoTouch0.0" />
      <frameworkAssembly assemblyName="System.Net.Http" targetFramework="MonoAndroid0.0" />
    </frameworkAssemblies>

The current workaround is to add the reference manually on 4.5 / 4.5.1.

The current problem with that workaround is that #145 clashes with this and puts in a reference to the net40 version of the assembly if it's absent at paket install time.

Related: #140 (similar conditions on NuGet package references)
Related: #154 (file pakets should be able to specify framework requirements too)

[forki]

Already fixed