feat: Add docs/readme.md + update crosslinks (#6700)

* complete translate list with the new languages appeared since hacktoberfest

* Create docs/README.md with the translations section

using root README.md as source. Links are adapted to this folder

Address EbookFoundation/free-programming-books#6698

* fix remaining url + translation items

- Portuguese (Portugal)
- Slovak / slovenčina
- Slovenian / slovenščina

Address EbookFoundation/free-programming-books#6698

* fix remaining url + translation items

- Portuguese (Portugal)
- Slovak / slovenčina
- Slovenian / slovenščina

Address EbookFoundation/free-programming-books#6698

* Add inclusiveness `dare to translate...` paragraph

* Add inclusiveness `dare to translate...` paragraph

* Move translations link target url to docs

* move translation links `bs`

* move translations link `en`

* move translations crosslink `es`

* move translations crosslink `fr`

* move translations crosslink `de`

* move translations crosslink `el`

* move translations crosslink `fa_IR`

* move translations crosslink `fil`

* move translations crosslink `it`

* move translations crosslink `pt_BR`

* move translations crosslink `ko`

* move translations crosslink `ru`

* move translations crosslink `id`

* move translations crosslink `zh`

* move translations crosslink `hi`

* move translations crosslink `pl`

* move translations crosslink `uk`

* move translations crosslink `vi`

* move translations crosslink remaining `HOW-To's`

* revert feature moved to #6688

* Remove the list from the top level. Leave `en` links

* use `previous languages` in root README

* Add more languages lists in root `readme.md`

* fix typo

* fix typo

* Update docs/README.md after translations paragraph

Less text is more

Co-authored-by: Eric Hellman <eric@hellman.net>

* Update README.md after translations paragraph 

Less text is more

Co-authored-by: Eric Hellman <eric@hellman.net>

* Update README.md preface translations paragraph 

Co-authored-by: Eric Hellman <eric@hellman.net>

* fix CONTRIBUTING target url commited at fd2b39151c

* Update docs/README.md preface translations paragraph 

Co-authored-by: Eric Hellman <eric@hellman.net>

* read me! said the boss ^^,

less text is more.

Co-authored-by: Eric Hellman <eric@hellman.net>

* remove "The inclusiveness is one of our targets, so "

Co-authored-by: Eric Hellman <eric@hellman.net>

docs/HOWTO-zh.md

@@ -1,4 +1,4 @@
-*[阅读本文的其他语言版本](../README.md#translations))*
+*[阅读本文的其他语言版本](README.md#translations))*
 
 欢迎使用 Free-Programming-Books（免费编程书籍）！我们欢迎新的贡献者；即使是在 Github 上首次提出拉取请求的人。如果您是其中之一，那么以下资源可能会有所帮助：
 
@@ -14,4 +14,4 @@
 
 即使您是经验丰富的开源贡献者，也有一些事情可能会让您绊倒。提交您的拉取请求后，GitHub Actions 会运行一个 linter（代码风格检测工具），经常发现间距或字母顺序方面的小问题。如果您获得绿色按钮，则说明一切准备就绪，但如果没有，请单击 "更多" 链接以查找 linter 不满意的地方。解决此问题并新增 commit 到您的拉取请求。
 
-最后，如果不确定要添加的资源是否适用于 Free-Programming-Books（免费编程书籍），请通读 [CONTRIBUTING](CONTRIBUTING-zh.md) 中的基本准则。([translations](../README.md#translations))
+最后，如果不确定要添加的资源是否适用于 Free-Programming-Books（免费编程书籍），请通读 [CONTRIBUTING](CONTRIBUTING-zh.md) 中的基本准则。([translations](README.md#translations))