Prepare 1.2.0 release (krahets#1585)

* 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.

Prepare 1.1.0 release (krahets#1274)

* Update bucket_sort.c

* Fix the comments in quick_sort.c

* Update the announce badge

* Sync zh and zh-hant versions

* Update contributors list.

* Sync zh and zh-hant versions.

* Sync zh and zh-hant versions.

* Update the contributors list

* Update the version number

Prepare 1.0.0 release (krahets#1044)

* Update the book with the thrid revised edition

* Fix a typo

* Update the contributors' information

* Update the mindmap

* Update the version number

Prepare 1.0.0b6 release.

prepare 1.0.0b5 release

Prepare 1.0.0b4 release.

Prepare 1.0.0b3 release.

Prepare 1.0.0b2 release

Update the chapter preface.