Improved chinese translation for homepage.

Squashed all commits from #19566.

Changes:
* Adding spaces between english and chinese characters.
* Translate "package" into "软件包".
* Change translation of "package manager" into "软件包管理器"
* Several minor changes.

Closes #19603.

Signed-off-by: Jack Nagel <jacknagel@gmail.com>
Japanese translation.

* Put <title> after <meta> to fix browser problems.

Closes #19744.
Merge remote-tracking branch 'upstream/gh-pages' into gh-pages

* upstream/gh-pages:
  Japanese translation.
  Improved chinese translation for homepage.