Modified Readme Doc.
Removed bbm-package from class file (it's just commented out). This was done as this package is rather special and few people may use it. More important it requires the installation of the package texlive-fonts-extra unter Ubuntu and would have needed additional installations in Prof. Quast's VM.

(cherry picked from commit 28635ed5ccd44f442e915d1f1dc56c21a692b20c)