Please improve configuration documentation

[BennieCopeland]

1. Can the settings defined in "CreateDefaultBuilder" be overridden by calling individual elements like "UseKestrel(opt => {})" afterwards?
2. Document "ConfigureAppConfiguration"
3. Explain the difference between "UseConfiguration" and "ConfigureAppConfiguration" (hint: UseConfiguration doesn't support reloadOnChange)
4. Document "ConfigureLogging"
5. Document the difference between configuring the Host vs configuring the Application

There are too many ways to configure, but are undocumented. See:
aspnet/Hosting#1430
aspnet/Hosting#1148

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Document Details

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• ID: 04eafd1b-403a-4aa3-48bc-78fed5b4d05e
• Version Independent ID: f35451f4-7c74-3ada-e969-b769428b94f4
• Content: ASP.NET Core Web Host
• Content Source: aspnetcore/fundamentals/host/web-host.md
• Service: unspecified
• Product: asp.net-core
• GitHub Login: @guardrex
• Microsoft Alias: riande

[guardrex]

Thanks @BennieCopeland for opening this issue. Let me get back to you in a day or two. We have 2.1 coming out around May 30, and you can guess what that's like. 😅🏃🏃🏃🏃🏃🏃

[guardrex]

Let me get back to you in a day or two.

Does 17 days count as "a day or two"? ... Sure it does!

We're discussing this issue now. I'm pitching a total rewrite of the configuration topic. As for this bit on overriding config in the hosting topic, I'll probably get to this one fairly quickly. I hope next week.

[guardrex]

You're GO for throttle up. 🚀

Let's use this issue to track the work. There will be a small PR to address the hosting topic, and the bulk of the work will be on the Configuration topic. I'll float an outline and questions for discussion here.