* add: kubernetes and docker play grounds

* fix: sorting in alphabetical order

* fix: remove trailing slash

* Create free-courses-id.md

* Update free-courses-id.md

* Update free-courses-id.md

* Update free-courses-id.md

* Update free-courses-id.md

* Update free-courses-id.md

* Update free-courses-id.md

* Update free-courses-id.md

* Added a link that leads to free-courses-id.md

* Update free-courses-id.md

add Tutorial Git in Bahasa Indonesia

* added cp sites

* removed trailing slash from toph url

* add Tutorial Python in Bahasa Indonesia

* add tutorial python in bahasa indonesia and fix error

* fix blank line

* add machine learning course in bahasa indonesia

* Update free-courses-pt_BR.md

* list alphabetized

Co-authored-by: NYehezkiel Gunawan <yehezkiel.gunawan@codify.id>

* Update free-programming-books-id.md

Hacktoberfest 2020

* Update free-programming-books-id.md

Fixed the link of "A MINDSTORMS EV3 robotok programozásának alapjai" to https://hdidakt.hu/wp-content/uploads/2016/01/dw_74.pdf

Co-authored-by: NStephan Schuberth <stephan.schuberth@de-cix.net>

* add more books and fix some old links

* fix some travis tests

* fix links

* try to fix the unicode order for Travis tests

* fix unicode order for Travis tests

* fix the unicode order for Travis tests 2

* fix unicode order for Travis tests 3

* fix unicode order for Travis tests 4

* fix unicode order for Travis tests 5

* Update kotlin playground

The current kotlin playground is obsolete.
Updated to the new playground link.

* remove '/' to satisfy linter

Always check the Travis-CI output!
Co-authored-by: NEric Hellman <eric@hellman.net>

* improvements to check_urls

make check have a more descriptive name
produce output file instead

* upload artifacts

* a

* change file to trigger test

* put things back

* Updated with refined link

* hope this space works

* Move a playground link to CSS section

FlexBox is a CSS feature.
This move is consistent with other files.

* Fix index in english free-programming-playgrounds

* Move a section according to alphabetical order

* Remove offline link pyfiddle.io

Shutdown confirmed: https://github.com/priyankcommits/pyfiddleio/issues/7

* Addes Javascript & Programming Fundamentals Books

Added Bengali language Javascript and Programming Fundamentals Books

* remove trailing slash on hostname per style guidelines

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

I made some orthography fixes

Changes include:
- Remove extra `/` for repo links
- Improve grammar so it flows better
- Make markdown follow standards

* update link for "Modern C" by Jens Gustedt, more authoritative

* same as before, but remove trailing slash for the linter

* added css notes

* Added Git and Nodejs notes

* fix broken urls

* trigger on pull request creation too

* allow certificate verify failed

some sites have misconfigured/expired certs

* adding back two links that were manually verified good

* Added AngularJS Notes

* Fixed the alphabetical order

fixes #3583

* [Update] free-programming-books-ko.md

Add raspberry pi free book link.

* [Update] free-programming-books-ko.md

Add links to raspberry pi free docs and change the spacing between lines.

* Fix the index

* Add Python Book (Arabic)

* Add CSS book (Arabic)

* Add HTML book (Arabic)

* Update ubuntu book’s link

Update ubuntu book’s link with the original source link

* Update UX book’s link

Update UX book’s link with the original source link

* add awesome_bot to check urls

* allow dupes

* make url checking dependent on commit message

* add web.archive.org to whitelist

cuz awesome_bot is having trouble with those links

* fix travis.yaml

* check urls

* need ruby

* another site to avoid

* check urls

* make regex more generic

* sudo deprecated

* make travis linter happy

check url

* try skip results

check url

* timeout was what was killing us

check url

* testing fixing urls

check url

* dont allow timeout

check url

* testing timeout

check url

* put fpb back

check url

* enable to check_urls on arbitrary files

check_urls:free-programming-books.md

* try again

check_urls:free-programming-books.md

* test again

check_urls:free-programming-books.md

* travis doesnt like :

check_urls=free-programming-books.md

* allow arbitrary number of files to be checked

check_urls=free-programming-books.md

* woops forgot to fix the trigger regex

check_urls=free-programming-books.md free-programming-books-en.md

* use for loop instead of xargs

check_urls=free-programming-books.md free-programming-books-en.md

* add documentation

* Link to the official site for Data Munging with Perl

* satisfy linter

* Update free-programming-books.md

* Update free-programming-books.md

* Update free-programming-books-ru.md

* Update free-programming-books-fa_IR.md

* Update free-programming-books-fa_IR.md

* Update free-programming-books.md

* Update free-programming-books.md