Visualstudio-docs: Open the O/R designer missing install instructions

[wittelw]

Save people hitting this page a HUGE amount of frustration by adding information from the following links (e.g. "How to Install" or "How to Enable") to the "Open the O/R designer" section:
https://developercommunity.visualstudio.com/content/problem/4616/linq-to-sql-dbml-designer-in-not-working.html
https://stackoverflow.com/questions/42485881/missing-linq-to-sql-classes-dbml-designer-in-visual-studio-2017-rc

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Document Details

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• ID: d1d50880-0c44-6bce-f39e-ac4d3d9f7430
• Version Independent ID: 41bcd05d-a7d1-28ec-75cc-208ec0b7f1a8
• Content: O/R Designer overview - Visual Studio
• Content Source: docs/data-tools/linq-to-sql-tools-in-visual-studio2.md
• Product: visual-studio-windows
• Technology: vs-data-tools
• GitHub Login: @gewarren
• Microsoft Alias: gewarren

[TerryGLee]

@wittelw Thanks for letting us know! We especially appreciate the links to the Developer Community and Stack Overflow, too. We'll get this page updated.

[wittelw]

@TerryGLee Thanks! I've also discovered the designer doesn't seem to work in .Net Core projects, but the generated code from a Framework app can be used in Core projects.

If this is the case and there isn't a better workflow perhaps you can add a note about this too (or the better workflow :).

[gewarren]

We will be revamping this documentation and downplaying LINQ to SQL in favor of Entity Frameworks.