2.2.2
add `proxy`.

2.4.0
add `youdao`.

2.4.2
translate.google()

2.4.4
simple README.rst
add github homepage

3.0.0
Due to incompatible code changes made in version 2.4.2, I should not upgrade the minor version number,
but the major version number. This is a modification. Thanks for Sabrina's reminding.

4.0.0
Implementing multiple translators is my pursuit, and the existing module name is ambiguous,
so upgrading the module name is something I have been exploring and thinking about.
Now the name `translators` is more in line with the meaning of the module itself,
and now I have no hesitation to upgrade, although the code upgrade and optimization is limited.

4.0.1
fixed "translators.google.cn"

