Add subfolders to Documentation folder

[blackdwarf]

As raised in #1075 by @akoeplinger, the Documentation folder's file
list forces the user to scroll way down to see the README.md. This
PR fixes that by storing the documents in separate sub-folders one
per hierarchy of related documents. Also changed
Documentation\README.md and root README.md to take into account
the new paths.

/cc @richlander @akoeplinger @terrajobst @kangaroo

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[dnfclas]

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[akoeplinger]

LGTM, thanks for doing this work 👍

Can we integrate the content of dotnetcore-intro.md into README.md as well? It's just a single paragraph so I don't think it warrants a separate file at the root.

[kangaroo]

LGTM

[blackdwarf]

@akoeplinger Agreed. @richlander are you ok with this suggestion?

[richlander]

Thanks for doing this @blackdwarf. Few comments.

• Including the brief intro in the readme is fine.

I'd prefer to following directories:

• installing -> install
• building -> build
• project-docs
• coding-guidelines
• botr
• decoders -> project-docs
• misc -> project-docs

Basically, I'd prefer not to use gerunds.

[richlander]

Looks like you should rebase master on your change. I merged in an update earlier tonight. Not surprisingly not compatible with a rename PR.

[blackdwarf]

OK, fixed the folder name as per @richlander suggestion, However, I cannot rename building to build, since build/ is in .gitignore. Don't want to mess with that at this point, so I suggest we just leave it as is, unless someone can educate me on the best way to do this. :)

[richlander]

@blackdwarf good point! Please ignore my aesthetics on that issue. It is not worth futzing with .gitignore to make it work.