l10n: zh_CN: for git v2.8.0 l10n round 1

Update 48 new translations (2509t0f0u) for git v2.8.0-rc0.

Reviewed-by: Ray Chen <[email protected]>
Signed-off-by: Jiang Xin <[email protected]>

l10n: zh_CN: review for git v2.8.0 l10n round 1

Author: jiangxin