l10n: de.po: Fix a typo

Signed-off-by: Wieland Hoffmann <themineo@gmail.com>
l10n: de.po: switch from pure German to German+English

This switches the translation from pure German to German+English.

Signed-off-by: Ralf Thielow <ralf.thielow@gmail.com>
Acked-by: Thomas Rast <trast@inf.ethz.ch>
l10n: de.po: translate 99 new messages

Translate 99 new messages came from git.pot update in
28b3cff (l10n: git.pot: v1.8.4 round 1 (99 new, 46 removed)).

Signed-off-by: Ralf Thielow <ralf.thielow@gmail.com>
Acked-by: Thomas Rast <trast@inf.ethz.ch