added django 3.1 official documentation to free-programming-books.md

* Added a pdf book on fortran. The book has tons of programing topics and gets in to programing history.

* alphabetize
Co-authored-by: NEric Hellman <eric@hellman.net>

* Update free-courses-en.md

* Update free-courses-en.md

* Update free-courses-en.md

* alphabetize
Co-authored-by: NEric Hellman <eric@hellman.net>

* Add D3.js courses, check_urls=free-courses-en.md

* Add d3.js courses, check_urls=free-courses-en.md

- With 2 new books
- Shifted one existing book in Angular.js to Angular
- Removed a book: https://leanpub.com/practical-angular from Angular.js because it's a Paid book
- Deno is now included under TypeScript, like in the Index

* added Python cheat sheets

Thanks for hosting this.
Just getting back into coding, and since I have been looking for resources for Python. 
I thought I would add what I have found. 

Happy hacking

* removed the spaces 

Hi sorry, it took so long to resolve this conflict. 
Actually took me a while to figure out how to do.

Thanks again so much for hosting this.

* alphabetize

* linespacing

* alphabetize
Co-authored-by: NEric Hellman <eric@hellman.net>

* Add Single page apps in depth by Mixu

* try to fix formatting

* fix formatting

* trailing slash
Co-authored-by: NEric Hellman <eric@hellman.net>

* free-programming-book-spanish

* Update free-programming-books-es.md
Co-authored-by: Nkadhirash <kadhirash@gmail.com>
Co-authored-by: Nkadhirash <kadhirash@gmail.com>

* Translating to spanish - Code of conduct

* touch

* alphabetize list

not sure why linter has never complained about other lists
Co-authored-by: NEric Hellman <eric@hellman.net>

* Updated free-programming-books.md with DBMS books

Added DBMS books

* Update free-programming-books.md

* Update free-programming-books.md

* alphabetize

also removed the adjacent tutorialspoint title- only a preview
Co-authored-by: NEric Hellman <eric@hellman.net>

* Added greek programming books and removed an SQL book with dead link

* alphabetize

* alphabetize greek
Co-authored-by: NRantosKonstantinos <k.rantos@users.noreply.github.com>
Co-authored-by: NEric Hellman <eric@hellman.net>

* güvenlik rehberi ekle

* Update free-programming-books-tr.md
Co-authored-by: Nkadhirash <kadhirash@gmail.com>

* duplicate heading
Co-authored-by: Nkadhirash <kadhirash@gmail.com>
Co-authored-by: NEric Hellman <eric@hellman.net>

* add free ebook java spring boot written in Bahasa Indonesia

* modified to raw link

* alphabetize

* pdf notation

* alphabetize
Co-authored-by: NEric Hellman <eric@hellman.net>

* Including cheatsheet for python

* alphabetize
Co-authored-by: NEric Hellman <eric@hellman.net>

* Add Swift courses, check_urls=free-courses-pl.md

* Add extra blank line, fix linter error

* Add NodeJS course, check_urls=free-courses-vi.md

* title case
Co-authored-by: NEric Hellman <eric@hellman.net>

* Update free-courses-pt_BR.md

* Update free-courses-pt_BR.md

* Update free-courses-pt_BR.md

* Update free-courses-pt_BR.md
Co-authored-by: NSeth <seth@elypia.org>

* Update free-courses-pt_BR.md
Co-authored-by: NSeth <seth@elypia.org>

* Update free-courses-pt_BR.md
Co-authored-by: NSeth <seth@elypia.org>

* line spacing

* remove non-free ourse
Co-authored-by: NSeth <seth@elypia.org>
Co-authored-by: NEric Hellman <eric@hellman.net>

#hacktoberfest "Laravel Portugal Live" Portuguese Podcast (Fixed filename) and added Ubuntu Portugal podcast (#4704)

* Fixed filename and added Ubuntu Portugal podcast

* Update free-podcasts-screencasts-pt_PT.md

* Update free-podcasts-screencasts-pt_PT.md

* Update free-podcasts-screencasts-pt_PT.md

* Update free-podcasts-screencasts-pt_PT.md

* Update free-podcasts-screencasts-pt_PT.md

* Update free-podcasts-screencasts-pt_PT.md

* Update README.md

* Update README.md

* Update free-podcasts-screencasts-pt_PT.md

* Update free-podcasts-screencasts-pt_PT.md

* Update free-podcasts-screencasts-pt_PT.md

* Update free-podcasts-screencasts-pt_PT.md

* Update free-podcasts-screencasts-pt_PT.md

* Update free-podcasts-screencasts-pt_PT.md

* Added 10web podcast

* Update free-podcasts-screencasts-pt_PT.md

* marker style

* titles from the resources
Co-authored-by: NEric Hellman <eric@hellman.net>

* Add iOS podcast

* alphabetize
Co-authored-by: NEric Hellman <eric@hellman.net>