Added links to korean docs (#5837)

* Implemented code of conduct korean translation

* Implemented CONTRIBUTING korean translation

* Implemented HOWTO korean translation

* Added English link

* Reverted MD syntax formatting

* Revert MD syntax

* Added HOWTO-kr links

* Fixed new line & anchors

* Fixed CoC

* chore(docs): fix all annoying markdown problems

Finish review EbookFoundation/free-programming-books#5837

* chore(docs): fix all annoying markdown problems

Finish review EbookFoundation/free-programming-books#5837

* Removed duplicated korean translation

* Revert bad md formatting

* Fixed inconsistencies

* Fixed indentation

* Added missing korean links

Co-authored-by: David Ordás <3125580+davorpa@users.noreply.github.com>

CONTRIBUTING-el.md

@@ -1,4 +1,4 @@
-*Διαβάστε το σε διαφορετικές γλώσσες: [Deutsch](CONTRIBUTING-de.md), [Français](CONTRIBUTING-fr.md), [English](CONTRIBUTING.md), [Español](CONTRIBUTING-es.md), **ελληνικά**, [Indonesia](CONTRIBUTING-id.md),[简体中文](CONTRIBUTING-zh.md), [繁體中文](CONTRIBUTING-zh_TW.md), [Português (BR)](CONTRIBUTING-pt_BR.md), [فارسی](CONTRIBUTING-fa_IR.md), [Tiếng Việt](CONTRIBUTING-vn.md), [Русский](CONTRIBUTING-ru.md).*
+*Διαβάστε το σε διαφορετικές γλώσσες: [Deutsch](CONTRIBUTING-de.md), [Français](CONTRIBUTING-fr.md), [English](CONTRIBUTING.md), [Español](CONTRIBUTING-es.md), **ελληνικά**, [Indonesia](CONTRIBUTING-id.md),[简体中文](CONTRIBUTING-zh.md), [繁體中文](CONTRIBUTING-zh_TW.md), [Português (BR)](CONTRIBUTING-pt_BR.md), [فارسی](CONTRIBUTING-fa_IR.md), [Tiếng Việt](CONTRIBUTING-vn.md), [Русский](CONTRIBUTING-ru.md), [한국어](CONTRIBUTING-ko.md).*
 
 
 <a name="contributor-license-agreement"></a>