Stepping stone for .NET Core migrations

[kant2002]

This is example of work what can be done to start moving into direction of .NET Core. That big work, but somethings which allow. I attempt to split onto commits, to indicate milestones.

• Migrate regular projects from packages.config to PackageReference This is basis for migrate project to new MSBuild format which in itself, required to try run code in ASP.NET Core workloads This should be improved even more by migration of WebApplications, but it require individually vetting that some Nuget packages does not contains content or other unsupported features.

Update Core,Data and Web.Framework to new MSBuild SDK style

• Services project cannot be converted due to reliance on Web Service (can be moved to separate project) -Projects inside Tests and Tools folders was not converted to due to significan changes which can prevent them from reviewing PR
• Unused files from Migrations was removed. These files was not part of the project.

I cannot run test for Data project due to #1870.

Related to #1235