[svn] Applied patch from Jim Hague:
- Forget cached group info when group database closed.
- Added list of 'forbidden' newsgroup specs.
- Fixed problem with article numbering if the overview file empties.
- Changed %i to %d in sscanfs (%i interprets leading zeros as octal numbers)
- New groups now always start numbering at article 1.
- Record newsgroup posting status. Enforce it at posting time.
Added --modify
- Added group deletion.
- Added wildmat code taken from INN