Add a Step 4 to OBO another API than Graph

> Please provide us with the following information:
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### This issue is for a: (mark with an `x`)
```
- [ ] bug report -> please search issues before submitting
- [ ] feature request
- [x ] documentation issue or request
- [ ] regression (a behavior that used to work and stopped in a new release)
```

### Minimal steps to reproduce
> Not applicable

### Any log messages given by the failure
> Not applicable

### Expected/desired behavior
> Demonstrated ability to call a downstream API.
Something similar to what you did with https://github.com/Azure-Samples/active-directory-dotnet-webapi-onbehalfof-ca

### OS and Version?
> Windows 7, 8 or 10. Linux (which distribution). macOS (Yosemite? El Capitan? Sierra?)
Windows 10

### Versions
> Same
> Same
> Same

### Mention any other details that might be useful
I used Step 2 as a baseline, got it to work, added a "CrmController" that I copy-pasted-adapted to receive a GET on /api/crm and issue a GET to https://myorg.crm6.dynamics.com/api/data/v9.1/accounts (a url that works well with Chrome's RestLet addon).
Using the WPF client (I added a button to call /api/crm) I bump in a consent flow.
I get a message box telling me that "consent is needed", I click OK, the browser opens and tells me that I have already consented to "TodoListService".
This leads me to believe that I think I am requesting a token for dynamics url, but in fact it requests it elsewhere.
I can see in the Visual Studio output it cannot find "user_impersonation" scope (a dynamics one) in the application which object id is "00000003-0000-0000-c000-000000000000" whereas dynamics is "00000007-0000-0000-c000-000000000000".

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