(occur-engine): Increment globalcount all at once after searching a buffer.

(occur-engine): Increment globalcount all at once after searching a buffer.
(occur-mode-map): Don't escape plain "o".

(occur-mode-hook): New variable.
(occur-fontify-region-function): Deleted.
(occur-mode): Don't use it.  Set up `font-lock-category-alist' instead.
(occur-fontify-on-property): Deleted.
(occur-engine): Use categories from `font-lock-category-alist'.