Aspnetcore.docs: new doc: Razor Pages Areas

[Rick-Anderson]

aspnet/Mvc#6926, aspnet/Mvc#6604
Scaffold the Identity UI and see how it uses areas.

Rename Areas in ASP.NET Core to Areas in ASP.NET Core for controllers
Before the intro, say this is for MVC controllers, see Areas for Razor Pages.

[guardrex]

Described by @DamianEdwards on the Standup :point_right: https://youtu.be/-EgE79M3tuc?t=34m00s

[Rick-Anderson]

@guardrex @scottaddie who wants this?

[mhmd-azeez]

@Rick-Anderson Can I take this? Is there anything I need to know first?

[Rick-Anderson]

@encrypt0r yes. Post an outline of the article here. @scottaddie do you have an idea for the outline?

[scottaddie]

I haven't had time to look at this yet. @encrypt0r Please provide your thoughts on a rough outline, and we'll review it.

[mhmd-azeez]

@scottaddie @Rick-Anderson
are you sure it's necessary to create a new page for "Razor Pages Areas"? Because all of the topics discussed in the current article must be duplicated in the new article as well. We can easily expand on the current page to include relevant information about "Razor pages" in the appropriate sections. This allows the users to see the whole picture more easily. Separating them might cause confusion.

Here are the changes that I think are needed:

Area features:

1. Add information about Razor Pages wherever appropriate

A typical folder structure for that using MVC areas looks like below:

1. Add "Pages" folder and some example pages to the folder structure

When MVC tries to render a view in an Area, by default, it tries to look in the following locations:

1. Add paths for pages in the listed locations

Link Generation

1. Add examples for Razor Pages.

2. Edit the article to make sure the flow between the topics are smooth

[Rick-Anderson]

@encrypt0r you're right. It's much better to have one topic on areas and update it so it applies to RP. Like you say

Add information about Razor Pages wherever appropriate

You're approved! Nice outline of proposed changes. I think you've hit everything.

[Rick-Anderson]

Moved to #9041