* Sync zh and zh-hant versions
* Update the list of contributors.
* Update time_complexity_simple_example.png
* Reduce size of the RGBA images for zh-hant version.
* Sync the zh-hant version of terminology.md
* Prepare 1.2.0 release
* Update the contributors list.
* Sync zh and zh-hant versions.
* Remove the polyfill.io link from mkdocs.yml
* Update contributors' info for code reviewers and en/zh-hant versions reviewers.
* Fix graph.md
* Update avatars for English version reviewers.
* Sync zh and zh-hant versions.
* Add Ruby and Kotlin icons
Add the avatar of @curtishd
* Update README
* Synchronize zh-hant and zh versions.
* Translate the pythontutor blocks to traditional Chinese
* Fix en/mkdocs.yml
* Update the landing page of the en version.
* Fix the Dockerfile
* Refine the en landingpage
* Fix en landing page
* Reset the README.md