Package with csproj and build as AnyCPU

[natemcmaster]

Remove makefile.shade and packages with csproj only
Build default .NET Framework assembly as AnyCPU instead of x64
Removes the dummy csproj for x86

[pranavkm]

I was hoping we could remove a lot of this when we do https://github.com/aspnet/Coherence-Signed/issues/401. Let me consult with the powers to be and see if we can make that change here instead.

[natemcmaster]

The package can target .NET Standard, but won't it still need to compile for .NET Framework and .NET Core?

[natemcmaster]

🔔. Can we take care of the ".NET Framework or not" question in a separate PR? This one is just about removing the dependency on Sake to pack.

[pranavkm]

I'd rather not make all these changes to the build if we can avoid it. If you'd like you could move the Sake reference to this project's repo.props once aspnet/KoreBuild#177 is addressed.

[natemcmaster]

Can you explain why you want to stick with Sake? I won't make a PR to add Sake to this repo. We are actively working towards removing it completely from our build system.

[pranavkm]

#90 should supersede this.