[svn] * src/util.c: Improve (correct) error detection when updating timestamp file. * src/content.h, src/content.c: Return Boolean success/fail from Cont_write. Also ensure cont.first isn't polluted in the event of a failed update. * src/client.c,src/control.c,src/fetch.c,src/noffle.c,src/post.c, src/pseudo.c: If Cont_write fails, don't do actions that need it to have worked. Typically, don't update first and last article numbers in group database. * src/server.c: If groupinfo.lastupdate is unreadable or corrupt, spot this and report it and give an explicit error when processing NNTP NEWGROUPS command.