Read in next newsgroups during idle time.  May not be able to store in
memory, but could write record to temp file, and do sort when actually
enter group.

Chdir to spool directory while running.

Add .rnlock checking.  (Use .newsrc.lck since rn use SIGEMT.)

Make N- get real previous group.

Make jd command save discussion for later.

Make t command get you to first unread article.

Make xerror do a longjmp to the code that resets the tty modes and updates
the .newsrc file.  Save a copy of the .newsrc file in .newsrc.bak.

