German translation, many translatable strings are missing

Problem/Motivation

Improve German translation, many translatable strings are missing in the voting plugins.

Proposed resolution

Update the German po file with all new and missing translations.

Remaining tasks

Created PO-files for German translation and faild to import them into localize.drupal.org.
To make sure we have our translations and not messed up translations from localize.drupal.org, we should maintain translations in the rufi profile. @localize.drupal.org I don't understand why my translations are not verified in your backend when I'm the maintainer of the module the translations are addressed to. The translated strings are all still in state "untranslated".

Complete the translation.
Import them with an update hook.