Added document "Layout of the mruby filesystem"

[dearblue]

This text was translated from Japanese to English by https://www.deepl.com/ .

---

• The text at the beginning of the file is an OpenBSD imitation (https://man.openbsd.org/OpenBSD-7.6/hier), but further tracing led to 4.3BSD NET/2 (https://man.freebsd.org/cgi/man.cgi?query=hier&manpath=4.3BSD+NET%2F2).
• I ran rake doc:update-index and it removed one blank line in the README.md file.
  It seems that some mistake was made last time and they got mixed up.

[dearblue]

The original Japanese file is available on Gist.
https://gist.github.com/dearblue/d1ce7d87f52c1b5ffacbddf1633a24b7

I will add another document as another PR in due course.
https://gist.github.com/dearblue/6c059bd77fa73863e3d6dd10976a44a5

[dearblue]

😿 prettier complains about the need for a blank line after a comment...

[jbampton]

😿 prettier complains about the need for a blank line after a comment...

You could add the README to .prettierignore

https://github.com/mruby/mruby/blob/master/.prettierignore

[dearblue]

Thanks for your suggestion.
However, I think README.md should be under the influence of prittier.
So I will update the task.

[matz]

"Layout of the mruby filesystem" sounds like a file system written for mruby. Probably "directory structure" is better.
However, I am not an English native.

[dearblue]

Thanks for the review.
I have changed the wording.
And prettier also passed verification.

[matz]

Probably “The mruby directory structure” is better.

[dearblue]

Changed.

[matz]

I am not a native, but we don't need this sentence altogether, IMO.

[dearblue]

Deleted.