* spam.el (spam-list-of-processors): use nil for nonexistent processors

(spam-group-processor-p): fixed function so it works properly
(spam-group-processor-multiple-p)
(spam-group-spam-processor-report-gmane-p)
(spam-group-spam-processor-report-resend-p)
(spam-group-spam-processor-bogofilter-p)
(spam-group-spam-processor-blacklist-p)
(spam-group-spam-processor-ifile-p)
(spam-group-ham-processor-ifile-p)
(spam-group-spam-processor-spamoracle-p)
(spam-group-spam-processor-crm114-p)
(spam-group-ham-processor-bogofilter-p)
(spam-group-spam-processor-stat-p)
(spam-group-ham-processor-stat-p)
(spam-group-ham-processor-whitelist-p)
(spam-group-ham-processor-BBDB-p)
(spam-group-ham-processor-spamoracle-p)
(spam-group-ham-processor-copy-p): functions removed with some
prejudice against unneeded code
(spam-report-articles-resend)
(spam-report-resend-register-routine): allow the group/topic
spam-resend-to value to override spam-report-resend-to
(spam-summary-prepare-exit): invoke spam-group-processor-p
properly now

* spam-report.el (spam-report-resend-to, spam-report-resend):
start with resend-to set to nil, and then ask the user if
necessary.  From Daniel Pittman <daniel@rimspace.net>.

* gnus.el (spam-resend-to): new group/topic parameter
(spam-process): move the OBSOLETE processors to the end of the
choices.