Bug#715334: Update Vietnamase translation

[Trần Ngọc Quân]

Hello again,
I pull from git, but vi.po still out-of-date.
I don't known why you don't apply my patch.
So I will send vi.po with minor edit.

Thank you
Trần Ngọc Quân.

vi.po.bz2
Description: application/bzip