[Tails-l10n] (review)[de] Tails installer: upgrade

Hi,
another branch ready for being reviewed by awesome muri ;)

https://gitlab.com/spriver/tails.git
branch: de_install_upgrade
HEAD commit: 38c8e6f Initial translation

Changed files:
wiki/src/upgrade/clone.de.po
wiki/src/upgrade/clone/overview.de.po
wiki/src/upgrade/tails.de.po
wiki/src/upgrade/tails/overview.de.po

Cheers!
spriver