feat: improve german translations

[bigbigmdm]

@wucke13 , thank you! Can you also check the following files: IMSProg_programmer/other/IMSProg.desktop IMSProg_programmer/other/IMSProg_editor.desktop IMSProg_programmer/other/IMSProg_database_update.desktop

IMSProg_programmer/other/imsprog.appdata.xml /IMSProg/blob/main/IMSProg_programmer/other/imsprog.database.update.appdata.xml IMSProg/blob/main/IMSProg_editor/other/imsprog.editor.appdata.xml

/IMSProg_programmer/other/IMSProg_database_update