Update Sample projects

[fiseni]

The sample projects are really old and outdated. We should delete them, and write new ones from scratch. We may have multiple projects

• SampleProject1 - The basic usage, utilizing the built-in repositories. Also, show some samples of how to use specs without repos.
• SampleProject2 - How to extend the specifications, builder, and how to put all pieces together.
• SampleProject3 - I want to demonstrate how to combine specs with custom repos, MediatR, Automapper (or any other mapper), etc.

We shouldn't push toward a given architectural style (e.g. clean architecture), that's up to the users. The projects should be as simple as possible, perhaps web projects using minimal API.