Fix German translations

[rabauss]

There are some minor errors in the german translation

            <trans-unit id="tl_news_archive.master.1">
                <source>Please define the master archive to allow language switching.</source>
                <target>Wählen Sie das Hauptarchiv um Sprachenwechel zu ermöglichen.</target>
            </trans-unit>
...
            <trans-unit id="tl_news_archive.isSlave">
                <source>Master archive is &quot;%s&quot;</source>
                <target>Das Hauptarchiv ist &quot;%s&quot;</target>
            </trans-unit>

[aschempp]

Fixed in 0386d76