add readme korean translation

[min-kim42]

I have verified that this pull request:

• has no linting errors (npm run lint)
• is from a uniquely-named feature branch and has been rebased on top of the latest master. (If I was asked to make more changes, I have made sure to rebase onto master then too)
• is descriptively named and links to an issue number, i.e. Fixes #123

Addresses #1350

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[catarak]

Yay this is so awesome! Looking at this again, I think that it would make sense to put this at translations/ko/README.md, and then link to this README in the root README. This allows for all of the README translations to be put in one folder.

[min-kim42]

changed the file structure accordingly! :-)

[catarak]

Great! I'd also like to link to this file from the root README (like under the first header). I'd just do it myself but I don't know how to say Korean in Korean so... I'll let you do it 😄

[min-kim42]

Thanks for pointing it out! I'll make a table with links just like All Contributors Readme. Just after the header p5.js Web Editor and before its first paragraph begins.

[min-kim42]

I have made a link to the translation/ko directory, so that a user could see the all the translated documents. Please let me know if you want something to be changed! :-)

[catarak]

I was playing around with the table formatting a bit and decided to take it out. Otherwise looks good and going to merge this!

[min-kim42]

Thank you for reviewing and organizing it! Yes, I agree that table didn't look great especially with just one box. A table could be useful when the number of supported languages grows to 10 or 20. Thanks for the merge!