Revert modifications from rpms/group/development (must match RH definition)
Add nedit to the list of standard editors
Add libXScrnSaver to interactive servers
rpms/development-base-tools: add python-devel and openmpi
rpms/document-viewers: add xdvik
Add rpms/virtualbox
Merge pull request #59 from jouvin/sl6.x-misc

sl6.x: various package group added/adjusted