* gnus-registry.el (gnus-registry-clean-empty-function)

* gnus-registry.el (gnus-registry-clean-empty-function)
(gnus-registry-trim, gnus-registry-fetch-groups)
(gnus-registry-delete-group): now groups that match
`gnus-registry-ignored-groups' will be removed from the registry
entries, not just ignored for splitting.  This helps clean up the
registry.  Also, `gnus-registry-fetch-groups' is a convenient way
to get all the groups a message ID is in.

* spam-stat.el (spam-stat-split-fancy-spam-threshold)
(spam-stat-split-fancy): changed "threshhold" to "threshold"
(spam-stat-score-buffer-user-functions): added :number custom type

From D Goel  <deego@gnufans.org>:

* spam-stat.el (spam-stat-score-buffer): Add a call to a
user-function allow user modifications of the scores.
(spam-stat-score-buffer-user): New function, to allow
user-computed modifications to the score.
(spam-stat-score-buffer-user-functions): list of additional
scoring functions
(spam-stat-error-holder): global temporary error holder
(spam-stat-split-fancy): use the new `spam-stat-error-holder'
variable