[SM-I18N] German Translation for helpfiles

[<nic...@mu...>]

Dear Squirrelmail-Team,

because we are using Squirrelmail in Munich and the "old" helpfiles were 
a bit "strange" for Germans, I fixed these files and attached them to 
this mail. Please note: I only attached the changed ".hlp" files for 
german. Copy these files in your "../help/de_DE" folder to provide 
translation.

Best Regards,

Nick Pleli