Add more case studies

[danieldanielecki]

As of v1.0.0 the only case study is related to Contoso, Ltd.

However, there are more we could cover:

• Windows Server 2016 virtual machine,
• City Power & Light,
• Proseware, Inc,
• Litware Inc,
• Coho Winery,
• VanArsdel. Ltd.

We can add them slowly, when the course will pick up.