[Tails-l10n] (Review) [de] shutdown.de.po

Hi,
Today just a small page: wiki/src/doc/first_steps/shutdown.de.po in
branch "shutdown".
I am currently working on the whole subpages of the section "first
steps", please be patient because it takes some time.

My git is like usually: https://github.com/spriver/tails


Regards,

spriver