* lisp/replace.el (occur-engine): Rename `globalcount' to `global-lines'

* lisp/replace.el (occur-engine): Rename `globalcount' to `global-lines'
for total count of matching lines.  Add `global-matches' for total
count of matches.  Rename `matches' to `lines' for count of
matching lines.  Add `matches' for count of matches.
Rename `lines' to `curr-line' for line count.  Rename `prev-lines'
to `prev-line' for line number of prev match endpt.
Increment `matches' for every match.  Print the number of
matching lines in the header.
(occur-context-lines): Rename `lines' to `curr-line'.
Rename `prev-lines' to `prev-line'.

Fixes: debbugs:14017