Add a Korean-translated README.md

[seoseonyu]

Context

• Added a Korean translated README.md for Korean users.
• For another language translation, I created a /docs folder and created a translation file in it.
• Added links to jump to language-specific documentation in each README.md file.

Choices

• We've created a translation document so that Korean users don't suffer from incorrect translations using Google Translate.

Test instructions

Checklist before requesting a review

• [v] I have performed a self-review of my code
• [v] I've added documentation about this change to the README.
• [v] I've not introduced breaking changes.

[thijsvanloef]

@seoseonyu Thank you for taking the time to translate the Readme! I did have 2 questions:

• The current README is quite often being changed, how would I change the korean version?
• Is it possible to name the folder ./docs/kr to reflect the korean TLD?

[seoseonyu]

First of all, thank you for managing that repository.

For the first question, I personally recommend using a combination of two methods.

1. subscribe to changes in the original via github watch to reflect changes as they happen.
2. assign a version number to the README.md to compare the current state of the original and the translation, and update it if the translation has a lower version.

Change ./docs/en -> ./docs/kr to reflect the Korean TLD.

If you have any additional suggestions, please let me know!